We do not build, supervise, hold funds, or decide whether work is complete. What we hold is the certificate, and the party who creates it is the party with the professional duty to assess.
What each stage covers and what it releases, agreed before work starts rather than negotiated when the money is due.
They record what they found. Not the contractor claiming progress, and not the owner assessing their own liability.
The same certificate, the same instant. There is no version that reached one and not the other.
Payment follows the certificate existing rather than following a separate approval that somebody has to remember to give.
Variations, rejected work and retention all still happen. What disappears is the argument about which version of the assessment is the real one.
What helps most is the real sequence on a project you worked on, including how long a certificate actually took.