Take a cage with apes. In the cage we hang a banana on a string, and put stairs under it. Before long an ape goes to the stairs towards the banana, but as soon as it even touches the stairs, all apes are sprayed with water.

After a while the same ape or another one makes another attempt, with the same result: all apes are sprayed. If later another ape tries to climb the stairs, the others will try to prevent it.

Now we take one ape from the cage and put in a new one. The new ape sees the banana, and wants to climb the stairs. To his horror all other apes attack him.

After another attempt he knows: if he wants to climb the stairs, he is beaten up.

Then we remove a second ape and replace it by another new one. The newcomer goes to the stairs and gets beaten up. The previous new ape takes part in the punishment with enthusiasm.

A third old ape is replaced by a third new one. The new one makes it to the stairs and get beaten up as well. Two of the apes who beat him, have no idea why you may not climb the stairs.

We replace the fourth old ape, and the fifth, etc. until all apes which ones have been sprayed with water have been replaced. Nevertheless, no ape ever tries to climb the stairs.

But Sir, why not?

Because thats the way we do things here, lad.