Originally Posted by Construct
That seems a little 'half-empty,' don't you think?
From my understanding, once you reach level 15, the game knows and it locks out that toon until you become a paid subscriber.
However, even if you do manage to keep your toon under level 15 somehow, if you come across any enemies (and you will, they're unavoidable if you're that underleveled cause even the slightest twitch from an underleveled player will set them off) the enemies will be able to pretty much one shot you each time and you won't be able to do ANY damage to them at all.
This means you won't be able to complete any more missions. But if you still want to go around exploring, nope, can't do that because every new area you find you get more experience points and pretty soon you're going to reach level 15 just through exploration and avoiding the enemies as best you can.
You're also locked out of all of the flashpoints that require you to be level 15+ which means the only flashpoint available is The Esseles or Black Talon depending on which side of the faction line you're on.
I could go on and on about how the game limits you, but I'm sure you get the idea by now.