Another, more prosaic term for fanboy. Also a clinically documented disease or syndrome, whose symptoms include excessively trying to get friends/family/strangers to partake in a product, espousing the many wonders of said product, and turning into a hell-spawned daemon when someone says that aforementioned product is shit.
It's a name to signify how much potential you may have. Brimming with talent but you aren't showing it.
It can also signify the fact that you have such latent talent and all you need is a small push to make use of your full potential.
Or it is just a way to say, you are a badass.
Me: Hey did you hear.
Friend: Hear what?
Me: The greatestLeague Of Legends player in his age group.
Friend: Yeah seems he even defeated one of the top players of our country in summoner's drift.
Me: He has so much potential he just needs a small push to become the best. He is truly a WalkingArrow.