OP - The information is out there. Do some reading and find out for yourself. Genetics and fast twitch muscles play a major role. There are reasons why Cavendish and Thor are sprinters and not climbers, (although Thor did some respectable climbing in this year's TDF) and they have nothing to do with fitness and training. Obviously, the better in shape you are the better you will perform. BUT.......... it all comes down to those fast twitch muscles. You either have them or you don't. It doesn't sound like you have them. Otherwise, you would be on here asking how you can become a better climber.