In Jujutsu and grappling we practice throws.
But for VT and street we lead into a throw with a strike - an atemi. This causes pain and distracts the opponent from resisting and countering.
In a clinch, we might use HKE before a throw. A knee before turning into uchi mata is a good example. A head before o soto gari is another.
Pain reflex is like when you put you hand on a hot stove and immediately retract your hand
Our first move causes instant pain and a visceral response in the opponent - this in turn allows and sets up our next move
The reason we don't practice randori-shiai judo-wrestling standing sparring for throws is because it doesn't develop the correct reflexes as we need to land a "blow before throw" to set up the move, not just relying on kuzushi unbalancing
