Personally I didn't think it was that hard. Then I released my first map and got a 0.3 score out of 10... lol. That was baaad.
In the end I feel it is necessary to put serious hours into learning the ins and outs of both JKA, the compiler, the map builder, the Quake engine, models, scripting, and such. Mapping is unlike other modifications to JKA in that you are building a three dimensional world in which all other modifications have to work.
Beyond all the technical aspects you have to learn how to make a map look good. This requires lots of creativity, HIGH attention to detail, knowledge of how to scale things and all different types of architecture. One mistake among thousands of brushes (brushes are the building blocks of maps, literally) and you won't be able to compile your map correctly. It could be a big gaping hole (forgetting to make the skybox) or a tiny crack in the terrain.
I would say you need to spend 100-200 hours before you can make a quality map, depending on your creative and mathematical abilities.
-- Kaeawc Farore
