It's nice for a challenge run when it proves to take a bit more time to do and if the reward is worth it.
Sorry for Necroreplying, but exactly this. It's the reason why I love Kegani Laboratory games, with all its flaws (I don't count the art style as part of its flaws, because the rough, and generic moeblob art style tickles my heart strings for some reason.)
It's the challenge of having overcome the mechanics intended for general "normal" play that really scratches some itch in my monkey brain, or maybe it's the lizard part? Idek.
Of course, I wouldn't spend more than 2 hours of my life playing a game where the only reward is one static H-scene at the end. Although I'm a degenerate, I do have my standards.