It’s interesting how the word estimate gets thrown around.

Different people seem to use the word in different ways – and do different things with the figures. John Rusk (from and I have come to the conclusion that there are at least three different definitions:

Prediction – how long you expect the task to take.

Target – a goal for how long you would like to take.

Commitment – what you publicly agree to.

Ideally, your prediction should be based on the best available information, and should only reflect the effort required to get the task complete. Note that political and budgetary considerations shouldn’t impact on your prediction - but they can pay a part in deciding your target and your commitment.

With these definitions, we can make some interesting observations.

… if your target is less than your prediction, then you’re hoping to get things done more quickly.

… if your commitment is less than your prediction, then you’re planning to fail – or to lose money.


blog comments powered by Disqus
Next Post
Real World Information Modelling: Naming  15 Mar 2009
Prior Post
Easier Enums  04 Mar 2009
Related Posts
Using Constructors  27 Feb 2023
An Inconvenient API  18 Feb 2023
Method Archetypes  11 Sep 2022
A bash puzzle, solved  02 Jul 2022
A bash puzzle  25 Jun 2022
Improve your troubleshooting by aggregating errors  11 Jun 2022
Improve your troubleshooting by wrapping errors  28 May 2022
Keep your promises  14 May 2022
When are you done?  18 Apr 2022
Fixing GitHub Authentication  28 Nov 2021
March 2009