I don't assume anything. I'm discussing the developers, and how they designed it.

I'm talking about the original games. The first ever game driven by child psychologists, based on what 12 year old boys love. Collecting things, and winning / dominating. They succeeded. The game has been wildly popular. The franchise continues of course, and with age will go through many ups and downs, but the base psychology still remains.

This is just fact. I'll try and dig up some sources. It's been a long time since #1 was released, but I'm sure there's still some info out there on the original development.