Why are puzzles so easy?

The difficulty ratings are incredibly inconsistent as well. I once got an "Extra Hard" puzzle where the solution was to windmill the opponent's pieces and deliver checkmate. There was absolutely no other move on the board that was even remotely sensible, and the windmill was clearly set up for you from the start. I've even had some extremely obvious mate in 1 (or 2) puzzles that have been rated "Extra Hard" for some reason.

On the other hand, I've seen plenty of puzzles not even rated "Hard" that were six or seven moves long and where there were at least five or six reasonable (but wrong) answers for each move, thus requiring you to look at it for several minutes to get the right answer without using hints.

you can change the difficulty in settings (on pc)