As men age, and the prostate enlarges, it's not uncommon for the intensity of orgasm to diminish. Medications can also interfere with the feeling. It's a bit unusual to have little reward in the teens and twenties. If you have, indeed, always been this way, you may never have intense orgasms as you would have already experienced that by now. On the other hand, if the intensity has diminished over time, it might be aging and/or medications.