Yes, I've always struggled with this when considering used cars (and to be honest, I've never actually bought one used in my whole life).
You find a good deal on a somewhat newer vehicle and the question that immediately comes to my mind: "Why did the original seller sell it in the first place?"
I personally find the sweet spot to be to buy new and then drive it for 4 to 8 years. Trade out before the residual value craters and maintenance and upkeep becomes significant.
A car payment is predictable. A major driveline failure or some other nagging issue is not.
that's how we develop our mechanical skills...out of necessity!