1 min lesson
Why period close is where it all comes due
Rebuild the main list in "Why period close is where it all comes due", then say what each item changes.
Step 1 of 2
Why period close is where it all comes duethe deadline that makes everything urgent
Close is the moment the four clocks have to agree for a period. Late usage, a mid-period upgrade, a missed webhook, an unapplied payment - any of them surfaces here under a deadline. The mature posture is to expect lateness and design for it rather than to pretend the period is truly frozen.
- Accrue for known-late usage. If you know events routinely arrive a few days late, estimate and accrue rather than under-stating revenue, then true up to actuals.
- Correct forward. A modification or late event after close is booked in the current period via credit memo or true-up; you do not reopen closed books.
- Make reconciliation a pre-close gate. The raw-to-rated-to-invoiced and cash-application checks should be green before you close, not discovered after.
Interview move
If you're asked to design any O2C component, volunteer its failure mode and detection unprompted: "here's the metering pipeline, here's how it leaks if dedup fails and here's the reconciliation that catches it." Pairing every design with its failure mode and its control is the exact judgment this solo, greenfield charter is screening for.