DaptinWhy this direction matters
A limit is useful only when the whole lifecycle agrees.
A product that offers storage, provider calls, AI work, or another finite service needs more than a counter. It needs to know which plan applies, whether the person belongs to it, how much a request may cost, whether capacity should be reserved, and how actual use is recorded.
The post-release source work connects those decisions instead of leaving admission, accounting, and completion as unrelated checks. Expression-based costs can relate product inputs to usage while plan membership and quota state provide the customer context.
The intended result is an explainable product rule: why a request began or was declined, whose allowance it used, what it consumed, and what remains.