Assuming someone secretly dropped off a game in my driveway and I know nothing about it (which never happens), it would depend. If it's a clean 6 month old Stern pro, I'm going to fire it up and play. If it's a 40 year old beater, I'm going to check typical problem areas first. Batteries, burnt/ loose connectors, blown fuses, stuff like that.
Pretty rare to get a game that you know nothing about. The vast majority of the games I've bought I've played first and looked under the playfield and in the back box. Know what you have before handing over the cash and you won't get any surprises when you get home.