One way to put it is (and how I explained it to a client once): if you do fixed price and estimate 100, but end up having 120 of work, then you'd need to quote 140 (40 padding) to the next project estimated at 100, just to make up for your previous loss. In the end the uncertainty costs everyone.
For people willing to find how to do better estimate, I can warmly recommend following Mike Cohn training:
One way to put it is (and how I explained it to a client once): if you do fixed price and estimate 100, but end up having 120 of work, then you'd need to quote 140 (40 padding) to the next project estimated at 100, just to make up for your previous loss. In the end the uncertainty costs everyone.
For people willing to find how to do better estimate, I can warmly recommend following Mike Cohn training:
http://www.mountaingoatsoftware.com/agile-estimating-plannin...
(and related books), as well as acunote which I use to estimate, plan and manage my projects:
http://www.acunote.com