Deferred Maintenance
Work a fleet knows is needed and has not done, usually because of budget, staffing or vehicle availability. A liability that accumulates quietly.
Deferred maintenance is the gap between what a fleet knows its vehicles need and what it has been able to do. It is a normal operating reality rather than a failure, and it becomes a problem when nobody is counting it.
In a public fleet it is often a budget outcome dressed as a technical one. A maintenance line cut mid-year does not reduce the work the vehicles need; it moves that work into next year, usually with interest, because a deferred repair often becomes a larger one. The saving appears in this budget and the cost appears in a later one, which is precisely why it is an attractive cut and why quantifying the backlog is worth doing before the conversation rather than after it.
Fleets that manage it well keep it visible as a number and a dollar figure rather than as institutional memory, and they distinguish deferred work that is a safety matter from work that is merely overdue. The first category is not a budget question.