Why Hubs?

I'm still new to mapping and new to playing Hexen, so there are many things I would like to learn to do, but as I look at the big picture this question comes up: why bother taking the time to learn how to build a hub-style Doom II map in Hexen format? I could build a Doom II map where you teleport to other buildings and hit switches that cause things to change back in a main building without using any scripting, so what would be the advantage of building a scripted hub made up of different levels?

You can change a hub level in-game and it will stay changed when you switch between levels and come back.

The main advantage is that a hub can be a lot bigger (and have a lot more active monsters) than a single level.

Herculine said:

I could build a Doom II map where you teleport to other buildings and hit switches that cause things to change back in a main building without using any scripting, so what would be the advantage of building a scripted hub made up of different levels?

One thing you would not be able to change with a high degree of accuracy is the position of enemies killed, nor remove corpses of enemies killed (if that was required in the changed sections of the map). In a hub, if you kill an enemy, move to another level, and return to the original level, the dead enemy will be in the same spot. If you wanted the changes to occur within a single level (instead of a hub), you wouldn't be able to do much with the corpses of the killed enemies. The same with decals created by weapon's fire (e.g., imp fire balls after they've struck a wall).

Remember that a hub is primarily intended to allow a player to revisit areas previously visited. If the area you are building is small enough that you can manage everything in a single map (i.e., what Gez said), or back-tracking is not necessary, then a hub is not needed. However, if you start building a large area that requires back-tracking, then not only can a hub be sometimes necessary, it can also help in managing map-specific objecives.