Before getting into DPI, let me tell you that mouse pad size is something most people don't think about when they buy a gaming mouse. They buy a good mouse, then use the small pad which came free with keyboard, and after a few days they feel the aim is not right in the game. Now the main reason...
Most of the people buy a mouse by seeing the look, the RGB light and the price, and the DPI number on the box is forgotten after only a few days. And with the cheap local mouse it is not even written anywhere on the box. So when a gamer wants to set the sensitivity properly or a designer wants...