I feel like most of the chess.com puzzles have a point: fork the rook and king with the knight, or exploit a pin. That makes them easier (or maybe my level isn't high enough there, yet). The lichess.org ones I often have no idea what to even try, and when I'm given the solution I still don't know why it's the best move (though looking at the "Spectator room" of the game can help). Sometimes the better move is only marginally better; like the computer assesses black as -3.4 instead of -3.6.