Capital and Operating Budgets
The two separate pots a public fleet draws from: capital buys the vehicle, operating runs it. They are approved differently, and that split shapes nearly every fleet decision.
Governments budget in two streams. Capital pays for assets with a long life and usually runs through a multi-year capital improvement program. Operating pays for the year: fuel, parts, labor, outside repair.
A fleet lives in both, and the boundary between them is where a lot of avoidable damage happens. Money saved in one pot often reappears as cost in the other, and nobody is accountable for the total. Deferring a replacement protects the capital budget and raises the operating cost of keeping an old vehicle running. Buying the cheapest compliant unit protects capital and hands the operating budget a decade of higher maintenance. Neither trade shows up in the budget document that made it.
The practical consequence for a fleet manager is that the strongest arguments are the ones that cross the line: showing what a capital decision does to operating cost, in the same table, over the life of the asset. That is the whole reason lifecycle costing exists as a discipline rather than as an accounting curiosity.
Fleets are also awkward in capital planning because they are many small assets rather than one large one. A bridge is a line item; two hundred vehicles on staggered cycles is a program, and programs are easier to quietly underfund.