Back when I was a kid, when I was playing an adventure game or a role-playing game, drawing your own maps was simply considered to be part of the game experience. Not only did many early role-playing games not have auto maps, but the designers often went out of their way to make sure that creating a map was a challenge. There would be nifty things like tele-porters and twisters and lots of interruptions by wandering monsters just to make sure you couldn't concentrate on figuring out why your map was wrong. Some of the text adventure games I played were even worse as often the maps were not logically put together. The first role-playing game that I played that had a map feature was Ultima 3, which happened to be the first Ultima game that I played. Even that game didn't have an auto map. Instead you had to buy things called Gems (which were expensive) and then peer into the gem (destroying it) to get a map of the current level of the dungeon.
More modern games now make the map for you. I can't exactly say when this started to happen or why, but I have a couple of theories as to the reason for this. The first theory is that a few role-playing games had this feature while others didn't. The games that didn't have an automated map feature started receiving complaints due to the lack of the feature. The companies getting the complaint letters added the auto map feature to their checklist of requirements. I come to this theory from personal experience. People rarely email me to tell me that they enjoyed any of my games, but if they have a complaint they are much less reluctant to email me and air the complaint. My games are free, so you must wonder how much worse it must be for the companies that actually charge people for games. My other theory, which might be the more accurate one, is the keeping up with the competition theory where other games had the feature so the marketing department added that feature to the list of required features so their games could remain "competitive". This is also the primary reason why so much software is bloat-ware.
The key question here is why exactly don't people like making maps? As a kid I found it to add to the gaming experience. Yet going by my email it is clear that people want an automated mapping feature. I have broken this down into three possible reasons and suspect that each gamer who insists on automated mapping falls into one or more of these three categories: too much like work, too prone to errors, or last page syndrome.
From a technical standpoint, map making is quite a bit of work. The reason I didn't mind it is that at the end of the game you had a physical object that could be used to show to your friends that you really did finish the game. Perhaps it is a sign of my age, but a home made map of all the levels of a game seemed to be an accomplishment that was much more satisfying than the end of game screen.
Anyone who has tried to make their own map has probably run into the second reason. In some cases the game just doesn't map out logically. In other cases, all the combat that takes place has made the map wrong because you forgot to mark a square or accidently marked a square twice or were mapping in the wrong direction. Figuring out where you made the mistake can be time consuming and very annoying.
The last reason probably is the most common. Today's society is very attention deficit, thanks largely to commercial television. Many players don't want to have to take all the time necessary to go through the level and make maps as they play. They want to get through the map as quickly as possible so that they can get to the next stage of the game as quickly as possible so they can finish the game as quickly as possible so they can spend their money and get the next game as soon as possible like good consumer sheep. With there being so much good quality content available I suppose that this attitude does reflect the current reality while when I was a kid I could only afford to get a few games a year so what games I got had to last. It wasn't that long ago that I was a kid so certainly things are changing fast.