Archville spamming, and overuse of traps in early maps.
After a while, its stops being a fun surprise, and becomes annoying, lazy fake difficulty that shows the creator didn't have any other fresh ideas for said map or wad.
(seriously guys, don't throw Archvilles into the first map of a wad on ALL DIFFICULTIES when you know you didn't give the player proper weapons to deal with them. Making the player run to the exit isn't fun.)