Shifty bureaucrats moving goalposts: not breaking out lane miles into patched fractional mile and full-width lane miles.
You will see that patching is more labor intensive per asphalt wear time, thus incurring greater city budget expenditure on average basis.
We actually finally have a great city controller in LA, Kenneth Mejia, who has been working his but off (and literally getting sued by the city) for trying to un-screw the complete lack of accounting that has taken place in LA's budget.
He's active on socials and would definitely be interested in a concept like this to correctly attribute and predict costs if you reach out.