Thomas Grip of Frictional Games, the creators of Amnesia and Soma, tries to get to the mechanical bottom of “Walking Simulators”. Comparing their core mechanism to other kinds of games centered around moving an avatar around, he concludes that it is probably not the walking itself that keeps players engaged. Instead those titles seem to require a certain “meditative state”. He is not content with assuming players will be wanting to reach that state of mind though. Instead he hints at new possibilities to densely pack the environment with important information, which Frictional seems to be aiming to explore in future games.
Walking forward is just a matter of pressing down a key or stick. And unless you are my dad playing a game, this doesn’t pose any sort of challenge at all. Your brain is basically unoccupied and the chance of your mind starting to drift is very high. Instead of being immersed in the game’s world you might start thinking of what to cook for dinner or something else that is totally unrelated to the experience the game wants you to have.
The article on the Frictional Games blog: https://frictionalgames.blogspot.de/2017/03/traversal-and-problem-with-walking.html