[revelio]

>> it is an estimate and should be treated accordingly.

That's where it all breaks down. What does "treated accordingly" mean? In reality it means the estimates can't be used for anything because they are always unreliable. There is no such thing as a reliable software estimate, ever, unless what you're doing is so repetitive that you're about to be replaced by AI.

But that's not why people ask. Instead, half the time you give an estimate it gets immediately turned into a deadline, even if you were promised it wouldn't.

The top comment on this thread is naive. The reason devs hate giving estimates or point blank refuse is because it is meaningless, that's not how the software business works. Analogies to plumbers and builders just reinforce the naivety. Guess what, blue collar work is only predictable for as long as it's highly repetitive which being physical in nature, it often is. The moment what you're asking for is "build me an underground railway using the latest technology" it turns out construction estimates are worthless too (see: Crossrail).

One reason tech firms crush their competition so reliably is they don't have an estimates-deadline culture, because they're run from the top by programmers who understand intuitively why they're pointless. Instead developers are incentivized by equity, bonuses etc to do the job as fast as possible.

[colinmorelli]

Estimates are about relative comparison, not specific accuracy. If you tell me one item will take a day and another will take 3 months, you can be wrong by several multiples and the information is still useful.

It’s less that I now have a specific endpoint, but rather I have a target (or multiple targets) at which I can decide if we’re on track and, if not, how I may want to change previously made prioritization choices.

If you tell me a day, then 5 days later if it’s still not done I may not rip you for being wrong but I may decide it’s time to pull the plug on that initiative since it no longer meets the criteria under which we agreed to do it.

I’m all ears for another proposal, but “just keep building stuff with no regard for how long any of it takes” is not much of a strategy and doesn’t reflect the way that decisions have to get made in the real world with limited resources.

[revelio]

Estimates for relative comparisons are more justifiable but rarely used, in my experience. And you can't bend on that stuff. The moment you say (to non developers), OK, I'll estimate X for task 1 and Y for task 2 they think, ah ha, if you can do estimates for this you can do estimates for all tasks.

Also and I cannot stress this enough, if you can make any estimates at all you're playing on easy mode. If the stuff you're programming isn't entirely rote boilerplate then you cannot estimate anything, ever, because your error rate will be measured in orders of magnitude not multiples.

Classic scenario: "how long will task X take?" ... "hmm well there's an open source library that claims to do X here, looks pretty easy to use, so maybe two days?". Some time later: "why is X taking 2 months and not 2 days?" ... "it turned out the library has some non obvious architectural limits we can't fix and which kill performance for our use case, so we have to write our own from scratch".

That sort of thing - you thought you could rely on another component and then you can't - can happen at any time, to anyone, and renders all estimates based on the assumed viability of that component meaningless. But you're always building on third party work. If you have absolute confidence in all your dependencies it, again, means you are doing repetitive work that isn't much different from your last task. Such works exists, I guess a lot of frontend dev falls into that category, but it's also highly susceptible to being automated away by better frameworks or AI.

>> it doesn’t reflect the way that decisions have to get made in the real world with limited resources.

My experience was the opposite actually, the big successful companies do exactly that. They may cancel projects if they seem to be no hopers, but they don't try and estimate up front how much a project will take because they don't think in terms of projects at all. If something is important, it gets staffed until it either stops being important or the team is beaten, at which point it gets unstaffed. If progress isn't fast enough they add more headcount. Everything is thought of in terms of relative resource flows, not timed Gantt charts.

[MrJohz]

> In reality it means the estimates can't be used for anything because they are always unreliable.

This seems like throwing out the baby with the bathwater. An unknown thing can still have bounds on it: I don't know exactly how far it is to the nearest supermarket, but it's further than 50m away and closer than 1km away. That's useful information: I know I'll be able to walk that distance, I know I can probably carry a reasonably heavy load back, and I can roughly estimate how long I'll be gone.

Fwiw, I agree with you that estimates are too often used badly by management to set up deadlines rather than genuinely make planning decisions, but I also think developers often fail to communicate their confidence levels when giving estimates. There is a material difference between "I know exactly what the problem is and what needs to be done, this will take two days" and "this looks like a pretty minor issue that will probably take two days, but it's touching a system I'm less familiar with, so it could end up going on a lot longer if strange things are happening there".