Probably it's a bad idea, though I'l bet there are good arguments on both sides of this discussion. There is always "wear and tear" to electronic circuits when you turn them on. For example, that's why lightbulbs often burn out right when you turn them on -- it's because the filament has worn thin from the "surges" caused by turning the power on. So, the less times you turn a light bulb on, the longer it will last. However, there is no standard for this. I'd say all electronics are designed to be turned on many times a day. But quality standards are not uniform, even within the same product line. Some electronics, such as cable box, have no moving parts, and generate so little heat, that I'd never turn them off. The same with an audio system, rather than turn the power off, turn the volume down, and stop all the moving parts. But somewhere common sense has to apply -- what is the cost of the wear and tear, versus, how much electricity are you using. A cable box costs pennies a month to operate. A TV on the other hand costs pennies an hour to operate. So if you're leaving the room for more than 10 minutes, you might consider lowering the volume on the radio, and turning a relative energy hog like a TV off.