In addition, masturbation comes in handy when you feel an erotic impulse but your spouse isn't there or isn't in the mood, or when you want an orgasm quickly without having to concern yourself with your partner's pleasure. Masturbation is neither infantile nor immature, and it's definitely not just for singles. Some women consider a mate's taste for pornography a form of infidelity or betrayal. That may be true, but most men who view porn by themselves use it to spice up their fantasies during masturbation. One's own fantasies can get old and stale, especially if one masturbates frequently.
Porn provides substitute fantasies.
It's a mistake for a woman to infer that a man's enjoyment of or need for porn implies any dissatisfaction with her or the quality of the sex in the relationship. Usually, porn is simply fuel for his fantasies during masturbation. See the previous answers. Masturbation rarely replaces partner sex. It's a sign of a robust sexual appetite, something many men think women lack.