A lot of discussion on estimation recently. A lot of great arguments but a lot of good old mistakes we’ve already went through. This brought me to a few random thoughts on estimating techniques.

1. Estimation technique which involves discussion between different people is better than one which just simply uses their estimates as input.
2. Using factual recorded historical data is better than basing just on experience.
3. Smaller tasks can be estimated way better than big chunks of work.
4. Every estimate starts with some kind of guess at the very beginning.

I know these should be obvious yet I’m surprised how often people:
– forget about them
– deny these are true

Then they head towards wild guesses with some magic number applied, which may have some sense but not when used instead of real estimation.