15. Not realizing you’re fighting enemies that will respawn indefinitely and wasting all your health and ammo trying to finish them all off
You weren’t supposed to win, you were supposed to run away. Unfortunately, the game decided to let you figure this out on your own. Since you’re a total fake badass and NEVER back down from a fake fight, you didn’t figure it out until you’d already unloaded clip after clip into the unending army of minions. Now you’re off to the next section of the game barely clinging to life. Annnnnnd it just auto-saved. Beautiful.