What the maintenance logs say after three years of the same release cadence.
Shipping on a fixed day removed most of the scheduling conversation, and the rest of it moved into the changelog.
The teams that kept a weekly rhythm reported fewer rollbacks than the teams that shipped whenever a branch went green.
Database migrations and anything that touched billing kept a human in the loop, on purpose.
Three signals turned out to predict a bad week, and none of them were code coverage.
Sustained backlog predicted an incident about two days out.
Retries climbed before error rates did, every time.
Large diffs correlated with rollbacks more than with defects.
The logs cannot say whether the cadence caused the calm or merely accompanied it.
Nobody has run the counterfactual, and nobody is volunteering to.