Ask what a household owns and you will hear about the cars and maybe the furnace. But most homes are quietly running a fleet: a mower, a washer and dryer, a dishwasher, a water heater, a refrigerator, a couple of power tools, a grill, and something in the yard with an engine in it.
Everything with a motor has an interval
Mowers want an oil change and a blade sharpen annually. Dryer vents need clearing, and a clogged one is a fire risk rather than an inconvenience. Water heaters want flushing. Refrigerator coils want vacuuming. None of it is difficult; all of it is invisible until something fails.
The list is the whole trick
You do not need a maintenance regime. You need an inventory, because once the machine exists in a list somewhere, the interval attaches to it and the reminder happens without anyone deciding to care about mowers this week.