FSJ has it right. When your customer faces a problem with a new product of yours, better apologize and get this product replaced free of charge rather then explaining he made a mistake. You'll make this guy happy, and in the meantime you'll learn a lot about potential misuse of this product. Hence its next revision will be even better, and you'll be able to thank your customer for his great contribution to the improvements.
" For the record, there have been zero problems with iPhone. Zero. Those "dead spots" aren't actually dead spots. Yes, people have brought some back and we've given them replacements. That's not because there was anything wrong with the phones. But it's easier to just give them a new phone and make them happy than to explain to them that they're screwing up when they use the phone, and that they probably need to have their big fat stupid fingers whittled down. FYI, all Apple employees who want or need finger-reduction surgery will get subsidies from the company. See your benefits representative. "
Full article here. Fun, as usual. Plus, read this amazing story about the guy who went to surgery in order to better use his new iPhone.