What causes car not to starter - besides the starter

Needs more detail about will not start. For "years" and I do mean years I have had to turn the key twice to start the car when warm. The solenoid for some reason the Bendix gear will spin the first time. Turn off the key and reengage the starter and the Bendix gear will engage the flywheel and start the car. The hotter the car is the more times I have to turn the key before it engages. I know I am taking a chance with the starter before it totally dies. That becomes another issue for another day. If you have any other symptoms you did not explain them to try and give you any additional suggestions.