Game collecting is immensely fun and I admit I really enjoy collecting games despite all the annoyances I face while doing it. That said, there are so many things that annoys us collectors but I'll just go over my personal top 3!
I'll always prefer to buy a game with no stickers on it even if it's a bit more expensive. It's maddeningly annoying when a you see stickers on games. Some stickers are easy enough to remove especially is they're on a plastic surface like most modern game cases but there are some stickers that fuse with the plastic and just won't bugger off no matter what you do to it. It's even worse if they've stuck it on a game's box because the box could tear when you're trying to remove it. You can't use any dissolving liquid on it either because that might cause even more damage. *sigh*
I always try to find games that are quite pristine and I'm sure most collectors do the same but this isn't very easy. Often it's just a minor scratch or two on the box and maybe some colour fading. However, sometimes I find games with scratched discs, cracked cases, missing manuals, torn boxes or covers and even some scribbling all over it and I just think to myself, "was the previous owner a blithering idiot?" because I can't think of any other reason why your game would be in such a horrendously bad condition!
I'm sure every collector has had to face this at one point or another. Unrealistic asking prices by people who think they know how much a game is "actually" worth. You try to tell them it's not worth that much but they're always very adamant, aren't they? This is especially common for older games. Just because something is a bit older and a bit less common, doesn't mean it's worth as much as a fortnight's holiday in the south of France!
There are quite a number of other things that annoy me but none as significantly as those 3. However, I still genuinely enjoy game collecting and I have no plans of stopping. There are some annoyances in anything we choose to pursue so at the end of the day we'll just need to deal with it. If you're reading this and you also enjoy collecting games, good luck game hunting mate!