Stilton: Are there any GOG games that are so bad you
have to play them, as opposed to just plain bad?
The ones for that would be bad games with a history to them. Bad indie games are so easy to find these days that there's no weight to them.
It's like Slender. You played it, and it was shit. I knew that would happen. It's garbage based on internet crap, so that was pretty much guaranteed. Will it matter years from now? Course not, it'll just be another sliver of filth related to stupidity that only mattered to idiots.
Master of Orion 3, Leisure Suit Larry Magna Cum Laude, Ultima 9. These games are fun because they signify the death of something people once loved. There's always an appeal to watching something good go off the rails as hard as possible.
Anomaly Defenders would also apply, but to a lesser extent because the series didn't have the weight. It just demonstrates the mutilation of a novel idea.
Then you've got your overblown, overhyped shitpiles like Daikatana and Fahrenheit. Games that blew so much smoke up people's asses it wasn't even funny, only to fail utterly in the end.
You can also go with titles like Earthworm Jim 3D or Simon the Sorcerer 3D, where the developers tried for the next big thing, only to turn what they had that was good into garbage for the sake of visual presentation.