Margarito at 154...Why did he go back to 147?

Why would he want to go up in weight when he has alot of options at WW? He still has a few big fights left at WW before he thinks of going up in weight. He's 7-0 against guys shorter than him, why would he give up that advantage?

he cant beat fighters his own size.

First of all, props to him for a great win. However, looking at their sizes, there was just too much size disparity. Marg was just too big for Cotto. And correct me if im wrong, but Marg already fought at 154 several times...Im just wondering why he didnt stay at that weight? Cuz he can make 147 and still be strong so it's a huge advantage.

First of all, props to him for a great win. However, looking at their sizes, there was just too much size disparity. Marg was just too big for Cotto. And correct me if im wrong, but Marg already fought at 154 several times...Im just wondering why he didnt stay at that weight? Because he got beaten?