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The XP rule is that a team is not allowed to work overtime. The only exception to that rule is that in the last week in a release, a team that is within striking distance of its release goal can sprint to the finish and work overtime.
Robert C. Martin • Agile Principles, Patterns, and Practices in C# (Robert C. Martin Series)
Overtime for salaried workers is a figment of the naïve manager’s imagination. Oh, there might be some benefit in a few extra hours worked on Saturday to meet a Monday deadline, but that’s almost always followed by an equal period of compensatory “undertime” while the workers catch up with their lives. Throughout the effort, there will be more or l
... See moreLister Tim • Peopleware: Productive Projects and Teams
That said, I believe work required beyond the scope of the contract (see No. 23, “Expect the Unexpected”) should generally be billed by the hour (at a rate stipulated in the contract).
Bonnie Siegler • Dear Client: This Book Will Teach You How to Get What You Want from Creative People
“Overtime is a fact of life.” This implies that the work can never get done in the amount of time worth allocating for it.