in & out of the tent.

If you take a 2 year old and a 4 year old camping and you want to keep the flies out of the tent, you make them zip it every time they go in or out. 

You think this effort will deter them from going in and out every 2.3 seconds.

But you forget that they love to zip and unzip the tent.

So how many times do you think they went in & out?

I don't know either, but at least they zipped the tent up each and every time.