Work at a pace that can be sustained indefinitely
Work at a pace that can be sustained indefinitely. A software development project is more like a marathon than a sprint. Attempts to increase the pace above optimum get only short term gains at the cost of long term losses.
SustainablePace is a core XP practice. In XP a team is not allowed to work overtime, except possibly immediately prior to a release. The establishment of a sustainable pace allows prediction of when work will be completed, without having to factor in short term gains and longer recovery periods. This practice explicitly recognizes that over the long term, a sustainable pace will be more productive than a variable pace.