Yesterday we practiced oji-waza (counter-attacking techniques) and in particular different kinds of nuki-waza (escaping/evading techniques). The waza we practiced were men-nuki-men, men-nuki-kote, and men-nuki-do.
First we practiced the timing and distance against a suburi-style straight men cut with no follow through. Then we practiced against an opponent who was trying to cut a conventional men-uchi with follow-through. This second exercise required us to use seme (attacking pressure) to induce our opponent to cut men.
In the beginning it was hard to perform the seme and then wait for the opponent to start their attack. Most people did the seme and then rushed, willy-nilly, straight into performing nuki waza. This caused their counter-attack to fail because it was too early, or occasionally it succeeded but was so early that it became debana waza (forestalling techniques). Of course there is nothing wrong with scoring using debana waza in a match. But during training we are trying to perfect all our waza, not just repeat the things we are good at.
With practice it became easier to induce the opponent's attack using seme, then with courage, allow them to start their attack and choose the right moment to evade and counter with nuki waza. The important thing here was having the courage to let the opponent attack, then use footwork to evade their attack while staying in a good position to deliver the counter-attack.
It is important to remember that we can't stop our opponent from attacking us, but by welcoming (迎え - mukae) their attack and observing what they do, we can easily counter any attack.