A mechanic was removing the cylinder head from the motor of a Harley motorcycle when he spotted a well-known heart surgeon in his shop. The surgeon was waiting for the service manager to take a look at his bike.

The mechanic called out across the garage, “Hey, Doc, can I ask you a question?”

The surgeon, a bit surprised, walked over to the mechanic, who was busy working on the motorcycle. The mechanic straightened up, wiped his hands on a rag, and said, “So, Doc, take a look at this engine. I open its heart, take the valves out, fix ’em, put ’em back in, and when I’m done, it works just like new. So how come I get paid so little, and you get the big bucks? I mean, we’re basically doing the same work, right?”

The surgeon paused, smiled, and leaned in closer. Then, in a quiet voice, he whispered, “Try doing it with the engine running.”