The Purpose Zones are yellow to represent caution. Throwing Purpose Pitches for a ball will be one of the most effective tools you can use as a pitcher.  It is equally as important to throw pitches off the plate inside as it is to throw strikes. Not every pitch has to be a strike to serve a purpose. This is a little known fact among coaches and pitchers alike.

Target Purpose Zones to keep hitters honest and prevent them from diving over the plate to reach an outside pitch. If the hitter recognizes a pitcher is afraid to throw in the Purpose Zone they can look for the pitch middle away, dive over the plate and actually pull outside pitches  This raises batting averages and power to all fields. 

Generally the pitcher owns the outer-half of the plate and the hitter has the edge on the inner-half. If you can't throw the Purpose Pitch, the hitter will begin to get comfortable in the batter's box. Once the hitter recognizes that you won't throw the Purpose Pitch they own both halves of the plate and they can reach a bigger percentage of the outer Go or Chase Zone.

The more Lokations you command, the less likely hitters will anticipate what Lokation the next pitch will be in.  If they can eliminate Lokations they know you cannot command from their minds, they have better possibility of getting the pitch and Lokation they're looking for.  This will make timing better and pitch recognition easier. 

The object of the Purpose Pitch is to move the hitter's shoulders, hips, or feet backwards.   The illustrations shown below are ideal hitter reactions to each level of the Purpose Zone fastballs.

 High Purpose Pitch Reaction

Mid Purpose Pitch Reaction

Low Purpose Pitch Reaction

Targeting the Purpose Zones is not intending to hit the batter in any way. The goal is to throw in the open area between the inside corner of the plate and the hitter to keep them honest. Catchers should recognize this area and be able to set up inside off the plate to make it easier for the pitcher to get the fastball inside. Aiming for an umpire’s mask can also be a good target if he is between the catcher and hitter.

The lower the purpose pitch is the further inside it has to be. The higher it is the more towards the inside corner it can be.  This is why the Purpose Zones go further towards the hitter, the further down they go

A hitter generally will not move out of the way of a pitch that hits the inside corner of the plate at or below the waist. But if you raise that pitch from the waist to the elbows of the hitter, he's most likely getting out of the way.  If the pitch is from the hitter's letters to his belt on the inside black of the plate, the pitch should work, but when you go below the belt on the inside corner, the pitch has to be further inside off the plate to move the hitter's feet.

The most useful Purpose Pitches are at the numbers 7 and 8.  These move the hitter back off the plate and will stand them straight up so they are more susceptible to the pitch down-and-away later in the count.  

Older pitchers can work on executing the fastball through the arm side 7 or 8 Purpose Zones and then the curveball or change up in the Go Zone in succession during bullpens. If hitters know you will throw the Purpose Pitch it be more difficult for them to keep their front side in on a breaking pitch.  

Both the Purpose Pitch and Go Zone Curveball are in the same area or "slot" when the ball is halfway to the plate so it looks like the same pitch which makes it harder for the hitter to recognize the pitch.  It actually takes them longer to recognize the pitch making timing harder as well.  If you never throw the Purpose Pitch, then the hitter can recognize the curveball early in flight because it is the only pitch that spends time in the Purpose Zone.   

For younger pitchers a change-up in the Go or Chase Zones can be just as successful following a Purpose Pitch. After you throw the Purpose Pitch the hitters timing is geared up for the fastball, so the change up looks slower afterwards and you have a bigger percentage of the outer part of the plate to work with.  The opposite of high and hard will always be slow and low.  Disrupt timing!