5. Having to backtrack for hours because you missed an item or key somewhere
Considering that today's games practically spoon feed you, it's amazing that this is still a problem. They won't let you skip the intro or hour long tutorial, and yet, they're totally cool with letting you blow right by that one crucial item. Attention game developers: I don't need help figuring out that spacebar lets me jump, but feel free to let me know if I'm setting myself up for a 3 hour backtrack. Mirror mode is only OK in Mario Kart.
4. Screwing yourself over by saving your game at a bad time
At the ripe old age of 13, I attempted my first play-through of Resident Evil: Code Veronica. At one point, I saved when I was low on ammo, health, and out of herbs (give me a break, I was probably wearing JNCOs at the time). Little did I know that when I left that safe room, I'd find Tyrant blocking my path to the mansion. I didn't have enough bullets to knock him down and my low health prevented me from knifing him. That was it. I only had room on my memory card for one precious save file and I totally ruined it. Eventually I got over my initial rage, regained my composure, and restarted the game. Eight years later.
3. A glitch prevents you from progressing
It's not fair! You faced the challenge and you won. You get to move on now. THOSE ARE THE RULES. Instead, you're stuck in a wall and NPC heads are spinning like they're Emily fucking Rose. For a short moment, you convince yourself that this is something that will correct itself. Soon enough. Any second now. Annnny second. Right now. Riiiiight now. ...No? Fuck.
2. Dying when you haven't saved
You went through a long, easy stretch and couldn't be slowed down by the five seconds it would have taken to pause and save. Such hubris! Then that surprise boss fight happened. Now that five seconds of save time seems extremely preferable to the several hours you'll be spending retracing your steps. And since you've just been traumatized, you'll be sure to stop and save every two minutes, further delaying your progress. Great job!
1. Accidentally hitting "yes" when an NPC asks you if you need them to repeat entire explanation
The worst thing about this is that it's most likely to happen to the people who hate it the most. The reason you accidentally clicked "yes" is because you were scrolling with such fervor that the words simply ceased to be words. If you had even skimmed the text, you would have seen the question and answered with a resounding "NO." Maybe it was your second play-through. Maybe the story was absolute bullshit and you wanted to get back to the gameplay. Either way, you're reading it again. And now that you're annoyed you'll probably scroll through it even faster, make a mistake, and be forced read it for a third time.
First nerd problems.