I usually read or watch walkthroughs. It's amazing how many new words I was able to learn while reading a Tomb Raider Anniversary walkthrough :D

If a game is too hard, I won't finish it. But I generally get bored with games before the end. I finished Legend of Dragoon once. ONCE. I get to the final area 3 or 4 different times. But the area is too grind intensive.

there comes a time when frustration and repeated deaths ruin whatever pacing and immersion the game had entertained you in the first place. I always go to google solutions to see if I can get past the block prior to just rage quitting. Even if a solution is found and I can progress, it takes a long while to get back into the game, and unless the game can bring back the fun it becomes more like a job just to finish it. As I get older the less I'm inclined to waste my time with a game that doesnt do it for me. Lifes too short to bother with annoyances, especially in entertainment. :)

My reflexes simply arn't fast enough to complete Snatcher, a lot of games I've completed you could increase your skill at playing them. Ninja Gadien 2 beat me with skill and reflexes, on easy...

I never finished Mafia, because of the damn fucking racing mission. You can not win it. Even cheats didn`t work!

Actually I think I completed the race. :P I had to haul ass like the fricken ghost rider though. I think the tough shootouts at the end beat me. Can't remember if I've completed Mafia 1 or not, I hate that. Nice little game though, I really should play it again.

I used <span class="bold">this trick</span> to finally beat this mission.

Bury them in a giant pit in Mexico.

On hold, indefinitely clogging my HD, usually until I buy a new computer. Then they become just a "saved game" backup file in a forgotten folder.

Wrong hiding place!  :-p

I finished Mafia. I can't remember much of the game but I do remember it had a very annoying racing part :D

Well, I read about it back then, but it didn`t work in my version of the game, maybe it was patched out!

Aquaria, final boss fight (sequence) - I don't have the patience to repeat and master several tough boss fights in a row without saving.

Marlow Briggs, final boss - I don't have the patience for fights in which 70% of the time is spent on evading the opponent's attack pattern and the damage I can do myself in the other 30% is so weak compared to the life energy of the boss that it takes ages.

Anodyne - the awkward jumping mechanics are game-stopping to me in the last(?) level. I have no clue how others were able to finish the game, it just doesn't work for me.

Knights of the Chalice - Not quite near the end yet, but far into the game, and I've become sick of the mechanics of no return, no resting, lots of wearing down by tough combat without any indication for how long you'll have to endure it before you're saved or hopelessly stuck in a dead end situation which requires you to replay the last hour or so. I enjoyed the game in general and would have loved to play on, but these design decisions ruin the game for me. Turning hard-earned xp into crafted items - and thereby hindering the level progression of your group in order to survive - becomes a necessity and I strongly dislike that idea in a RPG.

The thing is, I loved all those games before I got stuck and I can't bring myself to admit that I've abandoned them shortly before the end either, and it's bugging me, too ... Sadly, I have no better solution than the one mentioned by Telika, although in some rare cases, I "finished" the games by cheating (HL2-Ep2) or by watching the ending on YouTube (Gabriel Knight 2), if I didn't enjoy the last task, or I actually managed to complete them myself by trying again after a long break and suddenly finding that it wasn't as hard as I remembered it (Zeno Clash, Psychonauts).

Good call. I adore that game but it is ridiculously hard in parts.

I think I eventually cheated on the race part after five days. There is a left turn trick thing to get around it.

I had the retail box version, but I can't remember if I installed the patch or not...  According to <span class="bold">this post</span>, the patch makes the race much easier to win.