Maplestory Too much grinding

I played the game a while ago and I just can't understand how people can play that game and not get bored of it, i think i got to level 20 before i quit. And the highest level is lvl 200 or so, i quit at 20 because after around level 20 there is barely any quests to do so all you do is just grind non stop. Maple story isn't as popular as it used to be but it's still pretty popular and has a large and loyal player base. It is a big surprise to me how big it got and the amount of MMOs that decided to copy Maplestory by making pretty much clone versions of Maplestory. Maplestory does have a lot of content though such as the large amount of dungeons and bosses as well as classes and skills. The graphics aren't exactly the best in the world but the gameplay is easy, fun and simple.