The Principle of Kuzushi:

The principle Kuzushi is breaking your opponents balance. An important factor in throwing your opponent is known as Tai-Sabaki. it can be translated into how you manage your body to take advantage of leverage and keep your balance. This means going through the leverage motions involving your shoulder or hip as a fulcrum for throwing your opponent. Maintaining your balance is critical in order to successfully achieve this.

Problems coming from the Instructor An instructor who lacks ability to properly instruct will result in poorly trained Judoka. Whatever the reason it's important for students to ask questions and pay close attention to the information they are getting from their instructor.

And the most common source of the problem with poorly applied Kuzushi. The problem comes from Tori performing the throw. The solution to this problem can only come from the instructor paying close attention to the execution of the technique to show exactly where the lack of unbalancing the opponent is and how to properly take the opponent off balance.