Comparison
Flow efficiencyvsLead time
Flow efficiency
the ticket was open for nine days and someone was actively working on it for six hours of that.
The proportion of elapsed time in which work is actually being worked on rather than waiting. It is typically shocking the first time it is measured — figures under twenty percent are normal — and it reframes improvement work entirely, because shaving an hour off active work is pointless when eight days are queueing. It is the number that justifies work-in-progress limits to people who do not want to hear about them.
Full entry →Lead time
the request was made in March and reached customers in June, and the coding took four days.
The time from a request being made to it being delivered — the clock the customer actually experiences. It includes all the waiting: prioritisation, queueing, review, release windows. It is the more honest of the two flow measures because it counts the parts the team does not control, and it is usually dominated by them.
Full entry →