I’m worried that they put co-pilot in Excel

by isaacfrondon 11/5/2025, 8:54 AMwith 334 comments

by AkshatMon 11/5/2025, 1:30 PM

I find the contrast between two narratives around technology use so fascinating:

1. We advocate automation because people like Brenda are error-prone and machines are perfect.

2. We disavow AI because people like Brenda are perfect and the machine is error-prone.

These aren't contradictions because we only advocate for automation in limited contexts: when the task is understandable, the execution is reliable, the process is observable, and the endeavour tedious. The complexity of the task isn't a factor - it's complex to generate correct machine code, but we trust compilers to do it all the time.

In a nutshell, we seem to be fine with automation if we can have a mental model of what it does and how it does it in a way that saves humans effort.

So, then - why don't people embrace AI with thinking mode as an acceptable form of automation? Can't the C-suite in this case follow its thought process and step in when it messes up?

I think people still find AI repugnant in that case. There's still a sense of "I don't know why you did this and it scares me", despite the debuggability, and it comes from the autonomy without guardrails. People want to be able to stop bad things before they happen, but with AI you often only seem to do so after the fact.

Narrow AI, AI with guardrails, AI with multiple safety redundancies - these don't elicit the same reaction. They seem to be valid, acceptable forms of automation. Perhaps that's what the ecosystem will eventually tend to, hopefully.

by Dumblydorron 11/5/2025, 1:00 PM

Co-pilot and AI has been shoved at the Microsoft Stack in my org for months. Most of the features were disabled or hopelessly bad. It’s cheaper for Microsoft to push this junk and claim they’re doing something, it’s going to improve their stock far more than not doing it, even though it’s basically useless currently.

Another issue is that my org disallows AI transcription bots. It’s a legit security risk if you have some random process recording confidential info because the person was too busy to attend the meeting and take notes themselves. Or possibly they just shirk off the meetings and have AI sit in.

by glimsheon 11/5/2025, 12:11 PM

This reminds me of a friend whose company ran a daily perl script that committed every financial transaction of the day to a database. Without the script, the company could literally make no money irrespectively of sales because this database was one piece in a complex system for payment processor interoperability.

The script ran in a machine located at the corner of a cubicle and only one employee had the admin password. Nobody but a handful of people knew of the machine's existence, certainly not anyone in middle management and above. The script could only be updated by an admin.

Copilot may be good, but sure as hell doesn't know that admin password.

by simonwon 11/5/2025, 11:37 AM

This quote is pulled from a TikTok, I recommend watching the whole thing here: https://www.tiktok.com/@belligerentbarbies/video/75683800086...

(I pulled the quote by using yt-dlp to grab the MP4 and then running that through MacWhisper to generate a transcript.)

by Esophagus4on 11/5/2025, 1:06 PM

Hmmm the Brendas I know look a little different.

ā€œThere are two Brendas - their job is to make spreadsheets in the Finance department. Well, not quite - they add the months and categories to empty spreadsheets, then they ask the other departments to fill in their sales numbers every month so it can be presented to management.

ā€œThe two Brendas don’t seem to talk, otherwise they would realize that they’re both asking everyone for the same information, twice. And they’re so focused on their little spreadsheet worlds that neither sees enough of the bigger picture to say, ā€˜Wait… couldn’t we just automate this so we don’t need to do this song and dance every month? Then we wouldn’t need two people in different parts of the company compiling the same data manually.’

ā€œBut that’s not what Brenda was hired for. She’s a spreadsheet person, not a process fixer. She just makes the spreadsheets.ā€

We need fewer Brendas, and more people who can automate away the need for them.

by Havocon 11/5/2025, 1:34 PM

That mirrors my experience as well. LLMs get instantly confused in real world scenarios in Excel and confidently hallucinate millions in errors

If you look at the demos for these it’s always something that is clean and abundantly available in training data. Like an income statement. Or a textbook example DCF. Or my personal fav ā€žhere is some data show me insightsā€œ. Real world excel use looks nothing like that.

I’m getting some utility out of them for some corporate tasks but zilch in excel space.

by AmbroseBierceon 11/5/2025, 10:59 AM

Brenda has been getting slower over the years -as we all have-, but soon the boss will learn that it was a small price to pay for knowing well how to keep such house of cards from collapsing.

by jwsteigerwalton 11/5/2025, 1:58 PM

Many fears of ā€œAI mucking it upā€ could be mitigated with an ability to connect a workbook to a git repository. Not for data, but for VBA, cell formulas, and cell metadata. When you can encapsulate the changes a contributor (in this case co-pilot) makes into a commit, you can more easily understand what changes it/they made.

by d--bon 11/5/2025, 1:52 PM

It looks like the OP is thinking that AI causing errors in spreadsheets is going to make the whole economy collapse.

When tools break, people stop using them before they sink the ship down. If AI is that terrible at spreadsheet, people will just revert to Brenda.

And it's not like spreadsheets have no errors right now.

by alienbabyon 11/5/2025, 2:00 PM

Using ai does not absolve you from the responsibility of doing it correctly. If you use ai, then you better have the skills to have done the job yourself, and so have the ability to check the AI did things correctly.

You can save time still, but perhaps not as much as you think, because you need to check the ai's work thoroughly.

by Zigurdon 11/5/2025, 2:03 PM

It's verifier law.

Coding agents are useful and good and real products because when they screw up, things stop working almost always before they can do damage. Coding agents are flawed in ways that existing tools are good at catching, never mind the more obvious build and runtime errors.

Letting AI write your emails and create your P&L and cash flow projections doesn't have to run the gauntlet of tools that were created to stop flawed humans from creating bad code.

by andreww_youngon 11/14/2025, 12:51 PM

Being a copilot for Excel is an extremely challenging task. I've read many papers on this subject and feel that current technology is still far from achieving 90% or higher accuracy. If you frequently use ChatGPT to analyze Excel, I believe you also often encounter situations where it fails or makes mistakes, and this feature of ChatGPT (Code Interpreter) has been out for over two years now. Of course, ChatGPT is quite naive when handling Excel; it doesn't even bother to analyze how many tables are actually in a sheet, always foolishly treating each sheet as a single table.

by __mharrison__on 11/5/2025, 3:59 PM

Excel is the most popular programming environment in the universe. It has optimized the five minute out of the box experience so well that grade schoolers can use it.

Other than that, it is pretty horrible for coding.

by newscrackeron 11/5/2025, 5:06 PM

I feel what this article says based on some recent (non-catastrophic) experiences. I think I’m probably an above average user when it comes to Excel skills. I love spreadsheets. But I struggle with formulas like index, match, vlookup/xlookup and many others, and even more so when it requires nesting one within another and coming up with the underlying logic that leads to some complex nested formulas.

Over the past couple of months, I’ve tried some smaller models on duck.ai and also ChatGPT directly to create some columns and formulas for a specific purpose. I found that ChatGPT is a lot better than the ā€œminiā€ models on duck.ai. But in all these cases, though these platforms seemed more capable than me and could make attempts to explain their formulas, they were many a times creating junk and ā€œloopingā€ back with formulas that didn’t really work. I had to point out the result (blank or some #REF or other error) multiple times and they would acknowledge that there’s an issue and provide a working formula. That wouldn’t work either!

I really love that these LLMs can sort of ā€œunderstandā€ what I’m asking, break it down in English, and provide answers. But the end result has been an exercise in frustration and waste of time.

Initially I really thought and believed that LLMs could make Excel more approachable and easier to use — like you tell it what you want and it’ll figure it out and give the magic incantations (formulas). Now I don’t think we’re anywhere close to that if ChatGPT (which I presume powers Copilot as well) struggles and hallucinates so much. I personally don’t have much hope with the (comparatively) smaller and older models.

by snowwrestleron 11/6/2025, 1:37 PM

Some companies may have only one Brenda, but what really makes accounting work is multiple Brendas. In the case of my employer, we have a pretty small finance dept but we pay a big firm to come in once a year to check the books. ā€œBrenda as a service.ā€ (BaaS)

Brendas actually aren’t totally perfect so the tools between Brendas need to deterministically store and show their work so they can reliably check each other. If the tool itself has a Brenda baked into it—even if it’s a very good Brenda simulation!—it seems like a company could run the risk of losing that deterministic basis for double-checking. And therefore lose track of their accounting reality.

Some people will for sure over-trust the AI in the spreadsheet and make some dumb mistakes. Let’s all remember though that dumb mistakes in business are not illegal, and the whole point of a private market is to enable ā€œnatural consequencesā€ for businesses that make them. Some people will need to touch the hot stove of AI to understand how it could hurt them. I’m not sure there is any way to stop that, or even if we should.

by mikert89on 11/5/2025, 12:52 PM

10 billion dollars is probably going to be spent on automating excel, it’s going to happen

by eithedon 11/5/2025, 12:53 PM

Let it all crash and burn

by tempodoxon 11/6/2025, 3:02 PM

Deterministic formula evaluation is so boring. You can tell beforehand that the same input will produce the same result every time. With Copilot’s probabilistic formula evaluation you can never tell what the result will be, which makes things much more interesting and entertaining! Who wouldn’t want to have Copilot in Excel?

by like_any_otheron 11/5/2025, 3:43 PM

Excel doesn't need AI to ruin your work: https://www.science.org/content/article/one-five-genetics-pa...

by cjs_acon 11/5/2025, 10:55 AM

At some point, a publicly-listed company will go bankrupt due to some catastrophic AI-induced fuck-up. This is a massive reputational risk for AI platforms, because ego-defensive behaviour guarantees that the people involved will make as much noise as they can about how it's all the AI's fault.

by cssinateon 11/5/2025, 4:20 PM

I've partied with Brenda on the weekends, and let me tell you... SOMETIMES Brenda hallucinates.

But never during work hours. The woman's a saint M-F.

by teekerton 11/5/2025, 3:36 PM

Don't worry, in Teams it bothers me just one time a day, and with the click of a button it's gone... For another whole day.

by b3lvedereon 11/5/2025, 2:02 PM

"You know who's not hallucinating?

Brenda"

I don't know about that. There could be lots of interesting ways Brenda can (be convinced to) hallucinate.

by CheeseFromLidlon 11/5/2025, 6:27 PM

As an aside - isn’t it remarkable that we’ve introduced uncertainty and doubt into the knowledge processing layer? We have decentralised networks that run on Bayesian symbols for server-client models, CPUs that crunch Markov chains and now AI that hallucinates. On Deterministic Turing Machines.

by thisisiton 11/5/2025, 3:06 PM

Don't be like that. I work at a Fortune 500 and Brenda wants that co-pilot in Excel because it can help her achieve so much more. What is so much more you ask? Brenda and her C-Suits can not define it but they know for sure Copilot in excel will lead to enormous time saving.

by runakoon 11/5/2025, 1:29 PM

"the sweat from Brenda's brow is what allows us to do capitalism."

The CEO has been itching to fire this person and nuke her department forever. She hasn't gotten the hint with the low pay or long hours, but now Copilot creates exactly the opening the CEO has been looking for.

by intendedon 11/5/2025, 2:05 PM

Everything is now about verification.

AI may be able to spit out ann excel sheet or formula - But if it can’t be verified, so what ?

And here’s my analogy to think about the debugging of an excel sheet - you can debug most corporate excel sheets with a calculator.

But when AI is spitting out excel sheets - when the program is making smaller programs - what is the calculator in this analogy ?

Are we going to be using excel sheets to debug the output of AI?

I think this is the inherent limiter to the uptake of AI.

There’s only so much intellectual / experiential / training depth present.

And now we’re going to be training even fewer people.

At the end of the day I /customers need something to work.

But failing that - I will settle for someone to blame.

Brenda handles a lot of blame. Is OpenAI going to step into that gap ?

by danjlon 11/5/2025, 4:20 PM

Excel is programming. Spreadsheets have been full of bugs for decades. How is Brenda any different from a developer? Why are people scared when the LLM might affect their dollar calculations, and less bothered when it affects their product?

by motoboion 11/5/2025, 1:10 PM

Excel is the ā€œbeast that drives the ENTIRE economyā€ and he’s worried about Brenda from the finance department losing her job because then her boss will get bad financial reports

I suppose the person that wrote that have not ideia Excel is just an app builder where you embed data together with code.

You know that we have excel because computers didn’t understand column names in databases and so data extraction needed to be made by humans. Humans then design those little apps in excel to massage the data.

Well, now an agent can read the boss saying gimme the sales from last month and the agent don’t need excel for that, because it can query the database itself, massage the data itself using python and present the data itself with html or PNGs.

So, we are in the process of automating Brenda AND excel away.

Also, finance departments are a very small part of excel users. Just think everywhere were people need small programs, excel is there.

by Trasteron 11/5/2025, 11:09 AM

I'm actually not that worried about this, because again I would classify this as a problem that already exists. There are already idiots in senior management who pass off bullshit and screw things up. There are natural mechanisms to cope with this, primarily in business reputation - if you're one of those idiots who does this people very quickly start just discounting what you're saying, they might not know how you're wrong, but they learn very quickly to discount what you're saying because they know you can't be trusted to self-check.

I'm not saying that this can't happen and it's not bad. Take a look at nudge theory - the UK government created an entire department and spent enormous amounts of time and money on what they thought was a free lunch - that they could just "nudge" people into doing the things they wanted. So rather than actually solving difficult problems the uk government embarked on decades of pseudo-intellectual self agrandizement. The entire basis of that decades long debacle was based on bullshit data and fake studies. We didn't need AI to fuck it up, we managed it perfectly well by ourselves.

by skeptruneon 11/5/2025, 2:44 PM

Simon posting tiktok quotes on his blog was not on my 2025 bingo card.

by NumberCruncheron 11/5/2025, 5:03 PM

Is this not the guy who is on the payroll of Anthropic? Not because he is wrong, but because there is so much marketing going on in this space nowadays.

by more_cornon 11/5/2025, 8:06 PM

Me too. Theres no tool more trusted for accessible numerical precision than Excel. Lets sell all that goodwill for a shiny new magic bean.

by throwmeaway307on 11/5/2025, 5:59 PM

I'm worried Excel will go "enterprise only". and only LLM based interfaces will be enabled on the "office+windows" for consumers tier.

e.g. MS Access is well on its way. as soon as x86 gets fully overtaken by ARM, and LLMs overtake "compilers" (also taken enterprise only).. then things like sqlite-browsers (FOSS "access") will be an arcane tool of binary incompatible ("obsolete") formats

(edits: this worry has not been easy to type out)

by Fairburnon 11/7/2025, 2:48 AM

Dont use Excel? Unless you cant remove it or disable it assume this is the new normal. Act accordingly.

by diego_sandovalon 11/5/2025, 1:43 PM

I'm more shocked that someone is using TikTok to speak things that actually make sense instead of mindless memes.

by fancyfredboton 11/5/2025, 1:26 PM

This is transparent nonsense. People are very very happy to introduce errors into excel spreadsheets without any help from AI.

Financial statements are correct because of auditors who check the numbers.

If you have a good audit process then errors get detected even if AI helped introduce them. If you aren't doing a good audit then I suspect nobody cares whether your financial statement is correct (anyone who did would insist on an audit).

by sakesunon 11/7/2025, 1:52 AM

Somebody will soon name their AI agent Brenda.

by not_a_bot_4shoon 11/6/2025, 4:03 AM

I get it but I'm also tired of this meme

by byyoung3on 11/5/2025, 2:26 PM

Brendas hallucinate all the time.

by manuelzon 11/5/2025, 5:06 PM

I actually know Brenda.

by deburoon 11/5/2025, 5:37 PM

Luckily this is a capitalist society and usually mistakes in the private market resolve themselves because losing money is not a winning strategy.

by musicandpisson 11/7/2025, 2:42 PM

Yes.-)

by HeavyStormon 11/5/2025, 12:57 PM

Nay-sayers need to decide whether they fear AI because AI is dumb and will fuckup or because AI is smart and will take over.

by 133361096on 11/5/2025, 1:54 PM

320784788

by blitzaron 11/5/2025, 4:44 PM

another cheese that will affect the outcome of major tournaments, not a good look for microsoft

its like the xlookup situation all over again, yet another move aimed at the casual audience, designed to bring in the party gamers and make the program an absolute mess competitively