alt Hacker NewsHours is insane. But ultimately time is money and opportunity cost. Software engineering can’t be the only engineering where you ask the engineers how much something will cost or how much time it will take and the answer is “it’s impossible to know”. Even very inaccurate estimates can be helpful for decision making if they are on the right order of magnitude
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> Software engineering can’t be the only engineering where you ask the engineers how much something will cost or how much time it will take and the answer is “it’s impossible to know”.
Because it's not engineering at all. But even if it was, plenty of engineering projects are impossible to estimate - the ones that are doing something novel - and disliking that fact doesn't make it go away.
> Even very inaccurate estimates can be helpful for decision making if they are on the right order of magnitude
If what the business wants is an order-of-magnitude, they should ask for that; often (not always!) that's a lot easier.
I think software is one of those VERY rare things, where inaccurate estimates can actually be inaccurate by "orders of magnitude". After 20 years in the field, I still managed to use 2 months of time on a task that I estimated as 10 days.
The next natural progression of this line of discussion between "the business" and engineering is for them to agree on a time range as an estimate. Engineering doesn't want to say it'll be done in 6 weeks, but they feel okay saying it will take between 4 and 20 weeks so this estimate is accepted.
You can guess what happens next, which is that around week 8 the business is getting pretty angry that their 4-week project is taking twice as much time as they thought, while the engineering team has encountered some really nasty surprises and is worried they'll have to push to 24 weeks.
There's two things here that get overlooked.
First, people asking for estimates know they aren't going to get everything they want, and they are trying to prioritize which features to put on a roadmap based on the effort-to-business-value ratio. High impact with low effort wins over high impact high effort almost every time.
Second, there's a long tail of things that have to be coordinated in meat space as soon as possible after the software launches, but can take weeks or months to coordinate. Therefore, they need a reasonable date to pick- think ad spend, customer training, internal training, compliance paperwork etc.
"It is impossible to know" is only ever acceptable in pure science, and that is only for the outcome of the hypothesis, not the procedure of conducting the experiment.