Why seven-two offsuit is the worst hand
Three things go wrong at once. The gap between the seven and the two is too wide to make a straight — you would need four specific cards on the board, at which point the board is playing and your hole cards are decoration. Being offsuit removes the flush entirely. And the seven is low enough that pairing it usually means pairing into somebody with a better pair, while the two as a kicker loses every comparison it enters. Every other hand in the deck fails at fewer than three of those.