What separates a fair puzzle from a frustrating one

I've played puzzle games that made me feel clever and ones that made me feel cheated, and the line between them comes down to fairness. A fair puzzle hides its answer in plain sight. An unfair one hides it behind a rule you couldn't have known.

Luxora is a good example of the fair kind. Every time I got stuck, the solution was something visible on the board that I simply hadn't connected yet. That 'oh, of course' moment is the whole reward.

Bad puzzles pull tricks — a hidden mechanic, a button you couldn't have found, a timer that punishes thinking. Those don't test your logic, they test your patience, and they wear out fast.

When I review a puzzle game, I ask one question after every hard level: did I lose because I missed something, or because the game was hiding it from me? The best ones always land on the first answer.