When using good project management processes, the first profit is a decrease of schedule variance and so increasing predictability. The next profit is a shift in mean process performance leading to shorter and more cost effective time cycles.

CMMI Profits: Schedule

The basic input for good Project Management are good estimates of the to be performed activities. A good estimation method provides lower variance in estimates, which also leads to more reliable historical data, which can be used for future projections.

CMMI Profits: Estimations