Masturbation is way more enjoyable than sex. Sex is uncomfortable and awkward because you're constantly having to pleasure another person. You can't just be yourself because the other person might not like that, and the other person might do something that you don't like as well. It's stressful, and the pleasure you get from sex is dragged down by the social aspect of it. With masturbation, you can go at your own pace and stop when you feel like it, indulging in your own fantasies without judgement.