About estimation from the 'Mythical Man-Month'
I've read these in Mythical Man-Month.
First, our techniques of estimating are poorly developed. More seriously, they reflect an unvoiced assumption which is quite un-true, i.e., that all will go well.
Second, our estimating techniques fallaciously confuse effort with progress, hiding the assumption that men and months are interchangeable.
Third, because we are uncertain of our estimates, software managers often lack the courteous stubbornness of Antoine's chef.
Fourth, schedule progress is poorly monitored. Techniques proven and routine in other engineering disciplines are considered radical innovations in software engineering.
Fifth, when schedule slippage is recognized, the natural (and traditional) response is to add manpower. Like dousing a fire with gasoline, this makes matters worse, much worse. More fire requires more gasoline, and thus begins a regenerative cycle which ends in disaster.
The company I'm working currently has this habit of adding personpower to projects. We're hiring since I joined. I don't know what to think when I read these.