If the distance you move the pen is too small, the speed too slow, it can't recognize the gestures well and you can't operate it in the way you thought.
彼女はジェスチャーを交えて話した。
She accompanied her words with gestures.
我々はお互いにコミュニケーションするのに、言葉だけでなくジェスチャーも使う。
We use gestures as well as words to communicate with others.