Why would it cause damage?
Why doesn't it cause damage these days?
I mean, obviously keeping any electronic device on for too long will harm it, and gradually reduce its lifetime.
So I have to disagree.
Keeping it on during the night is unnecessary, you don't use it, and as I said before it is only going to cause problems. zigzag3143
You said it yourself, "the longer the computer is on the shorter the time till the next problem", you can't keep any electronic device on forever, there will be failures.
And I am not talking about "clearing memory" but hardware failures.