Think about your favorite games. While video games don't need a strong plotline to prove addicting (looking at you, Team Fortress 2), some of the greatest games in history feature engrossing plots, intriguing character design, and twists.
However, a game with a good story doesn't guarantee a satisfying ending. While everyone hopes their 40-hour-long play session will resolve cleanly, sometimes the developers have other plans, like pitting the player against a gargantuan evil baby to see who has the best rhythm.
Weird video game endings aren't necessarily boring, but they're usually nonsensical enough to leave the player stunned and confused about what happened. For better or worse, bizarre, left-field game endings feel like a complete 180° from the stories preceding them.