system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why do some men grow patchy beard, and other men grow full breards?

I'm 15 and I have a bit of a patchy beard and I want all the hair follicles in my face to actually have hair.
gpt
Generally, your ability to grow hair (both body and facial) will increase until, usually, your early-mid 20's. At 15, some people ( like <1%) can grow full, respectable mountain-man/viking beards. The overwhelming majority of people are in the same situation as you, only able to grow facial hair in small amounts (often only directly below the sideburns and the very bottom/center of your chin).

Best advice? Just wait.