Estimation – The Guessing Game
InfoQ offers an interesting read on agile planning and estimation. Here are a few key quotes 🙂
All numbers are based on assumptions. Your figures are only as good as your estimates and guesses – and there may be serious flaws in your assumptions.
If we approve a project based on a year’s worth of work, and we estimate it and we think it is all good, there is a lot of risk inherent in there. But also, and this is worse, we might ditch doing something really, really valuable for the company because we have clumped together all this value into a year-long project and we are making a really big decision – to go or no go – based only on that clump.
Big, up-front project thinking is essentially a lot of assumptions. According to the traditional assumption life cycle, we have business requirements, functional requirements, and they turn into development and then delivery. Actually, these business requirements that we come up with are all assumptions. We do not actually know these things are valid at all. We say, “Well, these are our business requirements. Let’s decide how we will deliver those and get some functional requirements around those”. These are just hypotheses