The biggest issue I've seen with cars is people making huge projects out of them. They need to sit back a little and take the car out, even if it's not "perfect", and enjoy it.
I've set myself a rule. Anything that I do to my car is going to have a time limit to how long it's going to sit around and not be drivable. Most of that time, I keep my down time to a day or two.
Point is, too many cars sit in the garage in various states of disassembly for years, when if they set their sights just a little more realistic and didn't take on too much at once, the car could be driven and enjoyed.