1. when you delete your save file after you've put hard work into completing the game
2. when your game crashed, and all the data is lost
3. when during a speedrun you somehow manage to go back to the very beginning of a game
Kyle: dude i accidentally did a reverse speedrun
Kyle 2: wait were you playing on my save file
Kyle: uhhh...
When you try to LOSE a game as quickly as possible.
"I did a reverse speedrun on Dark Souls"
"Must have been pretty anticlimactic"