That happens to me now too, I think it's because I'm old...
I think for me, it takes a special kind of game. I finished Mass Effect 1 without issue. As well as Skyrim and Factorio. But, I find it difficult to be motivated to finish many games I play. Their "charm" wears off too quickly and monotony sets in.
It also could have a lot to do with modern design philosophy. A lot of AAA open-world games use cookie cutter design to a fault. It's hard to find motivation to finish a 40 hour campaign with all that extra padding and filler content.
Same. Which is why I tend to play a lot of games that take me 1-2 days to complete.
You know what? I've started to notice this about myself too. Never used to have a problem finishing games, but now a game has to really suck me in for me to complete it. I've dropped quite a few games because I just can't be bothered with them.
Way too many games these days overstay their welcome. Often by padding the content with busywork and other tropes of modern game design.
More often than not I stop playin games because they bore me to death after fifteen hours.
I usually see everything in a game after 10 ~ 30 hours. The lifetime of the game can be extended depends on how well it gives me freedom (at this point, I don't care about META, just screwing around trying to break the game). It can even be further extended if the game can be modded. Otherwise? I'm done.
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