“In order to improve at anything, we need to know how well we are doing. Software develoment estimation is really a form of forecasting, and in forecasting “knowing how well we are doing” is known as verifiability.”
“The way most people do software estimation is not verifiable!”
“There is a way to make verifiable forecasts, and it’s the way meteorologists do it behind the scenes: forecasts must be probabilistic.”
“Even if we make dead-accurate 50 % estimations, people around us will not be happy…They will find it difficult what to make of coinflip estimations, where it’s just as likely the task will be late as early. The reason is that the cost of something being late is usually much greater than the benefit of it being early. In planning, we are generally more sensitive to tail risk. We can deal with this with a small change of procedure: make 90 % estimations instead, i.e. estimate the date where we are 90 % certain the task will be done before that date.”
“So what really makes a difference for prioritisation is not how quickly something can be done, but how much value the organisation gets out of it. That is what should be estimated, not how long it will take. It is really important that you estimate the value of all tasks you plan on doing, lest you may accidentally be stuck doing $100 tasks when you could be doing $5,000 tasks.”
https://two-wrongs.com/verifiable-software-development-estimations.html
Published on: 01-09-2023