You find out at closeout, ninety days too late. We land field hours and material costs against the estimate daily, so a job going sideways shows up while you can still fix it.

Actual cost arrives with the final accounting, months after the decisions that caused it.
Between kickoff and closeout, margin is a feeling. Nobody can name the number today.
The same kind of job loses money the same way, and the pattern only shows in hindsight.
Field hours and material costs landing against the estimate daily.
A job going sideways shows up in week one, while there's still time to change crews, pricing, or scope. This takes cost out by catching losses while they're small, and it sharpens every estimate after it.
A scheduled job lands the field hours and material costs against the estimate every night, and an agent flags the jobs drifting before the number gets big. Where it matters we build the checks in too: a daily job that tests the system and flags drift before you find it at month end.