However insufficient the explanation is, it's necessary from a Flat Earth Theory standpoint.
You can't go to the edge for perhaps one of three reasons:
1) You're forbidden by governments, conspiracy, armed guards, treaties, killer penguins, etc. (All of which have been thoroughly debunked)
2) Take the AE north pole centered mono-pole FE theory, the 3000 mile high, 32 mile wide sun doesn't shine beyond the wall, therefore the land is inhospitable to any human life as it is dark, incalculably cold and just downright deadly.
3) The flat earth plane is infinite so there is no edge.
In other words, pick your poison.