Worked retail customer service management for 6 or 7 years and in my experience it doesn't matter what it is coming back to the store, at LEAST 50% of the time there is nothing wrong with it, the customer either made up some BS reason for returning it because they thought you wouldn't take it back otherwise OR they're too dumb for the technology purchased and they can't get it to "work" ...and I say that as a person who has had to peel the fake LCD sticker off calculators people wanted to return because the numbers wouldn't change... Not just once either.
I'm not a fan of Asus myself but in my experience the vast majority of "tech problems" are ID-10-T errors, usually caused by a nut loose on the keyboard.