Hi, guys. I've had sexual experiences with several girls. Only one girl has achieved orgasm every time (and pretty easily), all the others seem to be very hard to satisfy, no matter how I try, in whichever position or ... When I and that easily-satisifed were doing that, she usually couldn't last for several minutes before she came. Although I felt pleased with this, my experiences with other girls are, to be honest, disappointing. Any girls have a clue why?