This is the same reason the Octogonal tower was made area explore.

You simply cannot get back to it for your corpse.

The dragon tower is worse, because you can teleport into it. This means if you teleport there, you have to wait at the pit no matter what. That's just crazy.

It also makes exploring there a far, far bigger risk than I think anyone wants to take. Gear is IMPORTANT, and difficult for some classes to get alone (if at all, comfort that evil conjurer buddy of yours).