Originally Posted by dguy6789
Link please. Until proven otherwise this is nonsense.
Have you ever pushed a phone's hardware? Seen how hot it got?
First of all there is battery drain. If you want to do something meaningful on your phone for a long time, you have to have it plugged in.
But this conflicts with another problem - heat. Phones can get extremely hot when running at full capacity. And sustained high temps are not only bad for the SoC, but they are especially bad for the battery. The same battery that has to be plugged in, charging and generating even more of a heat load.
A lot of phones have automatic shutdown or charge disabling in these situations.