Grinding's a thing. Whether your world-spanning MMO has a level cap that needs attaining (attention?) or you were just a few points shy of taking down that optional boss in your JRPG, players will, statistically, always take Just One More Turn to raise the numbers in any game with numbers to raise. It's basic psychology, and if it isn't quite healthy, it's not actually diseased.
Some games, though, create feedback loops with a fester in the mix. It's halfway normal to kill ten rats for ten hours to earn your next hero star and be one step ahead of the game--you've been playing the game for those ten hours, after all. But it's something else when the game provides a set of underdeveloped side-mechanics that allow an equal or superior progression for your character just in return for the investment of time and buttonpresses. Without any attempt to simulate the action or tactical thought of a traditional game experience, these compulsive number-raising cycles often amount to flicking repeatedly through menus or talking to skill-boosting characters over and over. And over. And over. Just because each time a number--even if it's a number significant to more "gamey" areas of gameplay--rises on a character sheet somewhere. In Boredom Simulator game activities, the play interacts with the game without any kind of thought, variation or excitement, just presses the same brief sequence again and again so that he can gain an advantage in another part of the game (unless, of course, the entire game is a Baredom Simulator).
The foremost examples would be almost limitless descriptions of skillgrinding in Elder Scrolls games (crafting 5000 copper daggers from vendor materials in Skyrim over several in-game weeks to reach 100 Smithing at level 1-10, autowalking into a wall for ten real-life hours to grind Sneaking to 100 in Oblivion, among myriad other possibilities). Similar examples can be cited for almost any RPG, somewhere along the line, whether it's summoning and killing your own pathetic creatures over and over in Baldur's Gate (did they yield experience?) or sprinting up and down the sneakcheck hideout wall in Wasteland to grind an entire party to 20th level in a few hours.