Much like a fingerprint or a snowflake, every pitcher is different. While all pitchers need control, command, velocity, and deception, how they check each box varies wildly. There are a plethora of different arm angles, release points, and other mechanical nuances a pitcher can use. Pitch selection plays an enormous role as well.
Some throw a 100-mph fastball, while others barely touch 90. Some have sharp-moving breaking balls that induce a lot of swings and misses. Others rely on pinpoint command to induce weak contact and get called strikes. Few pitchers have four or five plus offerings in their arsenals.