One of the biggest ones in mystery is “Why didn’t X simply Y”
They can literally just be stupid. Or ego driven. Etc.
There’s a great series of mystery games where the final villain even admits this exactly. He found evidence of a murder plot against the sister of his dead girlfriend, and instead of reporting it or detaining those involved, he let it almost happen. It was literally all so he could feel like a hero saving them at the last second, and he says as much directly.
One of the biggest ones in mystery is “Why didn’t X simply Y”
They can literally just be stupid. Or ego driven. Etc.
There’s a great series of mystery games where the final villain even admits this exactly. He found evidence of a murder plot against the sister of his dead girlfriend, and instead of reporting it or detaining those involved, he let it almost happen. It was literally all so he could feel like a hero saving them at the last second, and he says as much directly.