A task that fails raises an error. A task that stops running raises nothing. Quiet Guard tells you when one stops checking in.
->monitorHeartbeat('nightly-backup')
A scheduled task that crashes raises an exception, and you hear about it. A task that stops running raises nothing at all: the server is quiet, the logs are empty, and you find out the day somebody notices this month's invoices never went out.
Each task pings when it finishes. Past its period plus the grace you allow, it is the ABSENCE of a ping that raises the alert.
A macro on a task you already have. The ping fires on success, so a task that crashes stays silent and alerts exactly as if it had never run.
The first ping registers the task and never alerts. You set the period once you know what it is really worth.