It depends on the game.
See put a game infront of like half life, I wont care, becuase I dont care about it.
Npw make that game Fallout new vegas or a game I love, and I will try and get them all. Not because of the GS, but because some games I love I like to feel I did everything I could, unchecked achivements feel like they need to be completed. I am actually considering boositing a few just to complete a game or two because I enjoy the game but cant get them e.g in RDR you need to complete a game of liars dice, without losing a die, in a full game, no one can le3ave, problem is when someone is beat they instantly leave, another is the same but poker, I just cant get that one, and another called kingpin requires you kill l8 different people in one landgrab, I have only ever had 2 people try to kill me in landgrab.
Also if I feel its doable and the only one left e.g AC2 find feathers was all I needed, it could be done with a guide, and it had a reward (upon getting it I hated it).