Diapers

Why is it that when you just finish changing a diaper that they decide that they have to "go" again.

This seems to happen right after I change a really wet diaper and then they say "oh good, now that it is fresh and clean and Mom is comfortable doing something I think I will get her attention" This happened this morning. I have learned that Ron likes to do his business in the morning, so I wait a little bit to change his diaper until he has gone. I thought that I was being so smart and I'm thinking to myself "gotcha"! Well no sooner had I changed his diaper did he decide to do his business again. I think his thought process goes something like this.....

"hmmm I have to go, but I am wet, maybe if I go a little bit and then I will try again. Here she comes she can smell it!"
Now he rolls around and makes the changing process soooo much fun. We play and talk and try to keep him on his back so I can get him changed.
"Whew that was fun, ok now I am going to wait and then see what she does" He says to himself
"You know there is nothing better than a fresh clean diaper to soil and get my mom's attention again. I hate wearing these things and I hope that she lets me just roll around for awhile without any diaper"
So he gets changed and then he decides that if he rolls really quick he can get away from the diaper and not get one put on.

I don't know I think they know that these things cost money and they just want to remind us that "we are not cheap people"