That reminds me of the joke where a factory has a big machine break down. They call in a specialist to fix it.

The specialist looks at the machine for a moment, hits it with a small hammer and it starts working instantly.

But on being told that the repair cost is $500, the factory owner is outraged and asks how that can possibly be justified for less than a minute's work.

"Well, it's $5 for use of the hammer, $495 for knowing exactly where to hit the machine."