"If things slip a little, the developers can catch up."
A Schedule Math Question
The first set of requirements slips one day.
Predict the project end date.
Why Schedules Don't Work
The Cone of Uncertainty
Estimation in Reality
Why Schedules Don't Work
An estimate is the most optimistic prediction that has a non-zero probability of coming true.
Tom DeMarco, Controlling Software Projects, Prentice Hall, 1982
A schedule is a set of commitments based on estimates made at the time of least knowledge
But The Questions Remain
The Agile Alternative: Overview
Client maintain a backlog of
user stories,
most valuable stories first