Developing and maintaining accuracy is the order of the day early on in the developing of speech sounds.  Once a sound becomes stimulable, it needs to become consistently stimulable.  We need to go slow at first in order to develop the consistency.  But once the child is able to produce five in a row consistently, then you need to start pushing the speed.

When training for accuracy:

 

Golden Rule:  Accuracy first!  Develop speed while maintaining accuracy.

Keep training for accuracy until 10/10 are correct.  At this point you can consider training the sound for speed.

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