Once upon a time a very strong woodcutter asked for a job with a timber merchant, and he got it. His salary was really good and so were the working conditions. For that reason, the woodcutter was determined to do his best.

 
His boss gave him an axe and showed him the area where he was supposed to fell the trees. The first day, the woodcutter brought down 15 trees.

" Congratulations," the boss said. " Carry on with your work!"

Highly motivated by the words of his boss, the woodcutter tried harder the next day, but he only could bring 10 trees down. The third day he tried even harder, but he was only able to bring down 7 trees.

 Day after day he was bringing lesser number of trees down.
 

" I must be losing my strength", the woodcutter thought. He went to the boss and apologized, saying that he could not understand what was going on.

" When was the last time you sharpened your axe?" the boss asked.
" Sharpen? I had no time to sharpen my axe. I have been very busy trying to cut trees..."

 
That's right. Most of us NEVER update our skills. We think that whatever we have learned is very much enough. But good is not good when better is expected. Sharpening our skills from time to time is the key to success.