Break your opponent’s balance before attempting a throw or sweep.
Kuzushi is the Japanese term used to describe breaking your opponent’s balance. This usually involves a pull, lift, or tilt, and uses momentum to shift your opponent’s center of gravity. Essentially, kuzushi is breaking your opponent’s alignment by compromising their posture, structure, and base. Many throws and sweeps rely on the idea of kuzushi to be executed efficiently. Once you have successfully broken your opponent’s balance, the throw should be relatively effortless.
Attempting a throw or sweep without any kuzushi usually results in an unsuccessful attack, and even a risk of getting countered. This term is mainly a Judo term, but also translates well to BJJ, and ususally involves gripping the gi. However, even in no gi grappling, the term kuzushi can be used to describe breaking your opponent’s balance.
Every technique has a different kuzushi to set it up. For example, a forward throw like ippon seoi nage (shoulder throw) involves pulling your opponent forward onto their tip toes, which allows you to execute the throw easily since the weight of your opponent has been shifted forward. Backwards throws like osoto gari (outer reaping throw) tend to involve breaking your opponent’s posture and loading their weight on the leg you intend to sweep. Links have been provided below to demonstrate these throws.