More often than not, pitchers focus solely on velocity. Typically, scouts and coaches are more interested in the pitcher who throws 90+ rather than the pitcher in the 85mph range. However, velocity means very little if you can't locate your pitches. Hitters at higher levels can hit fastballs, regardless of velocity, if you throw it down the middle. My take-home point: Pitcher's need to be able to command the strike zone and their pitches
I believe command comes from 3 very simple factors:
1. A repeatable delivery
Repeating your delivery is somewhat of a controversial term in the pitching industry. While it may not be physically possible to repeat your exact delivery every single pitch, a similar release point on every pitch will allow for the consistency pitchers strive for on the mound. While there are many mechanical factors playing into the ability to have a consistent release point (which would take several posts to cover itself), consistency is necessary for pitchers to locate a pitch accurately Pitchers that have great command (Maddux, Wainwright, Halladay, etc.) all had/have the ability to throw each pitch from the same slot. There's a reason these guys were/are great pitchers. Study and learn.
2. The ability of the pitcher to "FEEL" their delivery and make necessary adjustments
It's vital for pitchers to be able to make adjustments during an inning, game, season, etc.. There will be times your mechanics will break down in some fashion. To maintain command it takes a special ability to diagnose your problem and fix it. When you, as a pitcher, miss low and away, do you know why? When you constantly hang a breaking ball, do you know what you did wrong, AND do you know how to fix it? Every pitcher has games when they struggle to throw a pitch for a strike. The difference between good pitchers and great pitchers is the ability to figure out WHY the pitch isn't being located and HOW to correct the issue. This is where “FEEL” comes into play.
I learned the term “FEEL” from Lantz Wheeler at BaseballThinkTank. He teaches that “FEEL” is a sixth sense a pitcher about their body while on the mound. When you throw an ideal pitch, do you have the awareness to recognize what your body felt like and the ability to replicate it or adjust accordingly.
For example: some pitchers struggle to keep the front shoulder closed long enough, causing them to “fly open” and often miss glove side. A pitcher who has a “FEEL” for their mechanics can recognize their shoulder is opening too soon and make an adjustment to keep the shoulder closed.
If you don't think this is a big deal, you're wrong. Pitchers who can make this adjustment during an inning and game are the ones who eventually get paid to throw a baseball.
When a pitcher repeats the throwing motion frequently and deliberately, neuromuscular patterns are built in the brain. This is a concept I picked from the late Dick Mills, and basically states a pitcher needs to throw countless pitches to the same location over and over again. This process builds a pattern in the brain, which in turn fires the muscles needed in the pitching sequence consistently locate a pitch. How can you train your brain this way to build these patterns? By throwing what I call blocked-over bullpens. In a blocked-over bullpen session, pitchers throw a specific pitch to a specific location repeatedly.
Here's a sample 60 pitch bullpen for reference:
3 sets of 5 FB arm side low
3 sets of 5 FB glove side low
3 sets of 5 FB arm side high
3 sets of 5 FB arm side high
I like setting up my bullpens to focus on one pitch that session, but don't feel like you have to do the same. Find what works best for your pitchers.
If you can improve in each of these three areas, you'll start hitting more corners and pitching to less hard contact, I guarantee it. Many pitchers made a living with great command by learning the art of pitching. Yes, velocity is great, but being able to command the strike zone is a quality that extends careers and keeps arms healthy.