I wanted to follow this practice routine by woohoojin, but I don’t know what the difference is between the overaim routine at 2:56 and deadzone routine at 3:16. Can someone explain it to me? https://youtu.be/JxP2y_q51IE

I was playing an unrated match with a couple of friends and during the buy phase I encountered a sound which sounded similar to the leak agents ultimate.... it also suddenly disappeared hahaha, I was quite confused at first then got excited...