Reluctancy to abandon a partially completed goal, even one forced upon the player.
"there are 30 "achievement" awards. 10 are hidden, 20 are specified. none are requirements for completing the game. some examples include "overflow the sink a second time" and "shoot the gun range target 100 times". none are prompted—unless you go looking for the page of awards, the game will not mention them unless you complete an achievement."
"the game has an achievement page that requires you to accomplish certain goals (such as popping chuzzles of one color across the board or completing a minigame under a certain amount of time), and achievements reward you daily with coins so it's beneficial to unlock as many as possible"
"Certain special outfits or frames for your avatar are available only after achieving some accomplishments in the game."
"There are individual player leveling and when you level you get items and bonuses. You can only get new areas (floors) of cats by completing another one."