Utilisation
The share of time a team, machine or system is busy. When work arrives unevenly, waiting times grow slowly at low utilisation and explode as it approaches 100%.
In plain English
In the standard queueing model, the average wait before a task starts equals utilisation divided by spare capacity, in units of the average task time: 1 at 50%, 4 at 80%, 9 at 90%, 19 at 95%. Idle time can't be stored, so bursts of work pile up when there's no slack. Teams that must respond quickly plan well below full utilisation.
Uncle Gary explains
Kevin's boss pushed the team from 80% to 95% utilisation. In the standard model, the wait before a one-day task starts grows from 4 days to 19.
Why it matters for your money
Being fully invested at all times leaves no slack for opportunities or emergencies. Spare capacity, like a cash buffer, looks wasteful on average and pays off in the bad weeks.
Where we tested it
Related terms
All glossary terms. Educational content, not financial advice.