Some people don't usually care about the temperatures of their devices. While others are freaked out to see the temperatures of their devices go up the numbers. These things are not that important to other people, it really does matter.
Temperatures of devices affect the performance of the device. The chips and the electronics that are installed in your devices are all configured to throttle down their power input especially computers. Smartphones and tablets are not usually configured this way. It goes like this:
More power = more performance = more heat
Less power = less performance = safer temperatures
They throttle themselves to be saved from the doom of melting. People often don't know this but now you do! You notice why the game runs fast at first then after about 1-2 hour/s of gameplay, the game just got slower and you'll be freaked out to know that something bad happened. That's just your video card saving itself from doom!
Another note to temperatures is that depending on the throttling powers of your devices, the electronics may have reduced lifetime. Because of heavy operation and temperatures, the chips will wear down when it conducts heat. You can't deny physics!