At 14U, I see many girls who cannot control their change up, if they have one. Not being able to control it is almost the same as not having one. Probably the biggest issue I see around here is girls throwing the backhand flip change. I sometimes call this the butterfly change up. The pitch comes out high and is easily recognizable by a good batter. Sometimes--with the help of an umpire--it can float into the strike zone and get called. Most of the time I see batters spit on the pitch. Other times it floats in belt high and gets crushed. Still other times the pitch ends up rolling on the ground because the girl's timing was off on release (girls almost never get brush contact at release with this pitch IME).
As someone who has called pitches for several girls on our old team, you end up getting handcuffed. You might throw it to show the batter something different when you are ahead, but know in warm ups that you are not going to be able to call the pitch for a strike and that if you throw it with runners on base they are just as likely to advance on a wild pitch. If they throw it too poorly, pretty soon you aren't calling it at all. Then you just hope they can spot their fastball, but chances are the batters are eventually going to time them up as your pitcher becomes one dimensional.
As with all pitches, it takes a lot of work to throw a high-quality change up that has great deception.
As someone who has called pitches for several girls on our old team, you end up getting handcuffed. You might throw it to show the batter something different when you are ahead, but know in warm ups that you are not going to be able to call the pitch for a strike and that if you throw it with runners on base they are just as likely to advance on a wild pitch. If they throw it too poorly, pretty soon you aren't calling it at all. Then you just hope they can spot their fastball, but chances are the batters are eventually going to time them up as your pitcher becomes one dimensional.
As with all pitches, it takes a lot of work to throw a high-quality change up that has great deception.