He inspected the engine very carefully, from top to bottom.

After seeing everything, the engineer unloaded the 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 the giant ship was $20,000 to the ship owner.

"What?!" said the owner.

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

The answer is simple:

Tap with a hammer: $2

Know where to knock and how much to knock: $19,998

The importance of appreciating one's expertise and experience...because those are the results of struggles, experiments and even tears.

If I do a job in 30 minutes it's because I spent 20 years learning how to do that in 30 minutes. You owe me for the years, not the minutes.