Once, a scientist put five monkeys in a cage.
He also put in a ladder, and on the top of the ladder, were some bananas. 

One of the five monkeys casually climbs up the ladder and tries to take a banana. 

At that moment, the scientist sprays the rest of the monkeys with water. 
This scares them and they pull the first monkey down. 

After a while, all the five monkeys stop climbing the ladder.
Because as soon as they do, the scientist sprays water on the rest of the monkeys. 

Now the scientist interchanges one of the old monkeys from the cage with a new one. 

This monkey sees the banana and tries to climb up the ladder.

But as soon as that happens, the rest of the monkeys pull him down, without even the scientist spraying them with water.  

This monkey doesn’t know what happens if they take the banana.
He just knows that as soon as he begins to climb the stairs, he gets beaten up. 

Piece-by-piece the scientist replaces all of the five monkeys. 

Now the cage has five new monkeys. 

They have no idea what would happen if they tried to climb the ladders, no idea what happened before them. 

But if any one of the five monkeys try to climb the ladder, the rest of them pull it down.
No one knows why.
Except, that this is how things have worked.

Question everything that you do that doesn’t make sense.