How GTM Inboxes uses this term
GTM sequences tiny-batch launches after readiness, smoke tests, and seed-placement evidence pass, with an explicit operator go/no-go decision recorded before the batch and a review of results before any volume increase.
Why small first sends win
Seed tests use controlled mailboxes; prospect mailboxes behave differently. A tiny batch is the cheapest way to observe real receiver behavior while keeping any failure recoverable with the replacement and recovery workflows.
Scaling after the batch
Review bounce codes, placement signals, and replies from the batch before approving the next volume step. Each increase should be a decision backed by the previous step's evidence, not a schedule.