Duration (project management)
Duration should not be confused with work. E.g. it takes three days for a snail-mail letter to arrive at point B from point A, whereas the work put into mailing it may be 0.5 hours.
Strictly speaking, the phrase Duration of terminal element X is 5 days is incomplete. It fails to specify the following:
- the probability with which the completion is expected in the time allotted (since any estimate is only a prediction about the uncertain future, see critical chain)
- the resources to be used (sometimes using more resources or different resources speeds things up)
- the assumptions which were made
- the author of the estimation
- the date the estimate was made
- the work schedule of the resources
So the improved statement could read:
- I, Marek Kowalczyk, as of 27 March 2005 strongly believe that if I fully applied myself to competing terminal element X and worked 8 hours a day every day, including holidays, and had all the materials at hand, then I would have completed it in 5 calendar days.' See metamodeling.
It may seem unwieldy to use such complicated statements, but lack of detail often leads to misunderstanding.