They do both. Evaluate the better moves and also think more deeply. Chess masters have great visualization of the chess board. I as a noob am unable to think 4-

They do both. Evaluate the better moves and also think more deeply. Chess masters have great visualization of the chess board. I as a noob am unable to think 4-5 moves ahead even if I really try hard. But pro players can visualise more than 10 moves easily.