Cost, budget and profitability
Know what the project costs while you can still do something about it
Time logged against a task, day rates against a person, and a budget line that updates as the work happens. When a project is heading past its budget you find out in the week it starts drifting, not in the month-end review.
Cost visibility is role-gated throughout, so the delivery team sees progress and the people who should see margin see margin.