I have noticed when I masturbate that if I use lotion of some other form of lube and really concentrate on the head I cum alot quicker and it's a more powerful orgasm than if I just concentrated on the shaft and stroked it back and forth. Something else I notice is if I do it long enough but don't cum, it starts to get soft even though i'm still super aroused. I have to stop a minute and let it get really hard again. If I just masturbate using my shaft and not touching the head it stays really hard. I know the tip has millions of nerve endings and i'm wondering if they are being over stimulated and it causes it to lose some feeling for a minute which makes it not as hard. I can still ejaculate when just playing with the head and it's very pleasurable but it's actually semi hard not fully hard like it should be. Same thing with sex. My wife dries out but her own natural lube feels the best. When she gets dry, she uses light love and it gets super wet but it's like i'm not feelings as much as I was when it was just her natural lube so I have to back off a second and let it get super hard again. It's weird. anyone else notice this? Also when I cum just rubbing the shaft, I shoot alot farther and alot more than I do when i'm just rubbing the head but it's not as intense of an orgasm.