Every engineer ships better features after a week on call. Here is what changes.
We started rotating product engineers through on-call not to spread the load, but to spread the lesson. A week carrying the pager teaches things no design review can.
You feel the cost of complexity
When you are the one woken by the feature you shipped, you design differently next time. The clever edge case that saved a day of work becomes the 3 a.m. page that cost a night of sleep. On-call turns abstract "operability" into a personal incentive.
You learn what users actually hit
The pager is a direct line to reality. The failure modes that fire at night are rarely the ones you imagined in planning. A week on call is a week of unfiltered feedback about where your product is fragile.
- You start adding the log line you wished you had during the last incident.
- You build the feature flag before you need to disable something in a hurry.
- You write the runbook while you still remember why it matters.
Empathy becomes design
The engineers who have carried the pager build more observable, more resilient features — not because they were told to, but because they have felt the alternative. Operability stops being a checklist item and becomes a reflex.
The trade-off
Rotating product engineers through on-call costs some feature velocity. It buys features that do not page anyone at 3 a.m. Over a year, that is the better trade every time.