I think many misconstrue gesture drawing for barely coherent scribbles. But I object. I admit that I used to think the same but after taking a gesture drawing class I've found it to be very rewarding.
Gestures are supposed to be quickly done but that doesn't give permission to throw out all accountability for a well designed and appealing drawing. In fact, it requires more so because all strokes must be executed with precision, accuracy (in that the resultant shapes must be believable and work together), and with energy. Gestures push you to see the "line of action" (I like to call it the "curve of action" because energy is not static but dynamic) and to let go of all the distracting details. It gets you to see big shapes and to design them so they work with the over all pose (I like to call this 'rhythm') and at the same time be appealing in itself.
I, by no means, claim to understand or even perform the gesture with mastery but, all concepts and theory aside, it's REALLY FUN!
Here is a small small sample of many many gestures I've done.