The prison in the beginning was supposed to be the
tutorial level as well as be the equivalent of a
Vault. You're not locked in your room all day, so you
can wander around and talk to other prisoners. I really
didn't like it in BG2 or Lionheart how someone else
came in to save my pansy ass. I'm the player,
therefore I get to be the hero.
However, just before your own plan is complete, the
prison is attacked by the mysterious NCR-looking guys.
This is not a "Unknown force rushes in to miraculously
save the PC" situation. You *already* had things in
hand; it's just that these dudes happened to interfere
with *you*. Furthermore, these dudes don't
specifically care about you.
Once the attack has occurred, the PC's free to leave
or stay. Unlike in BG2 or Lionheart, no powerful force
chasing you for nefarious purposes. The prison's
mainframe will eventually self-repair and start
sending out retrieval bots to go grab any prisoners
who wandered off, but it's not a life-or-death
situation. Most PCs will deal with the prison
supercomputer just to get it off their backs. Of
course, in doing so, they'll find out more about
what's going on.
The prison was also intended to be a town-like area
the PC could build up. After all, it's a pretty safe
place in the wasteland, and many of the prisoners
don't *want* to go anywhere else. There's food and
water and big thick walls all around. We were thinking
the PC could use his skills to bring in supplies and
make improvements and basically turn the prison into
its own town.