A mechanic was removing a cylinder head from the motor of a car when he spotted a well-known cardiologist in his shop.

The cardiologist was there waiting for the service manager to come and take a look at his car when the mechanic shouted across the garage, “Hey doc, want to take a look at this?”

The cardiologist, a bit surprised, walked over to where the mechanic was working. The mechanic straightened up, wiped his hands on a rag and asked,

“So doc, look at this engine. I opened its heart, took the valves out, repaired or replaced anything damaged, and then put everything back in, and when I finished, it worked just like new. So how is it that I make $48,000 a year and you make $1.7 million when you and I are doing basically the same work?”

The cardiologist paused, leaned over and whispered to the mechanic…

“Try doing it with the engine running”.