The result is that you get the most out of your penetration. With the woman’s pelvis tilted, her partner can go deeper, hitting spots that would have otherwise been unaffected. With a little maneuvering, you can hit her G-spot, and she will be primed for her nerve endings to come alive.
I think everyone worries about being a dynamo in the sex department. For many—especially the penis-carriers among us—the inability to offer up an all-night-waking-the-neighbors-fest of sexual ecstasy creates tons anxiety and concern. I blame movies, which paint a pretty picture because they are fantasies, not reality.