Fix the engine

A giant ship's engine broke down and no one could repair it, so they took it to a engineer with over 40 years of experience.

He inspected the engine carefully, from top to bottom. After seeing everything, the engineer unloaded his bag and pulled out a small hammer.

He knocked something gently. Soon, the engine came to life again. The engine has been fixed!

7 days later the engineer mentioned that the total cost of repairing was $ 10,000 to the ship owner.

"What ?!" said the owner.

"You did almost nothing. Give us a detailed bill."

The bill:

Tap with a hammer: $ 2

Know where to knock & how much to knock: $ 9,998

Lessons to Learn:

The importance of appreciating one's expertise and experience ... 

The words "it's easy" and "that's all", should be set aside. Why? Because maybe the experience is the result of struggles, experiments and even tears.

Like above:

If someone can finish a job in 30 minutes, it's because he spent 10 years learning how to do it in 30 minutes. You pay for those 10 years, not 30 minutes.