Say, there is a big tree in my garden. It casts a lot of shadow, so it makes my house ïnside very dark. At one day, I decide to chop it down because I got so annoyed to have to put on the lights by day, even in the summer. After a good night of sleep, I have forgotten that I did chop the tree and why I did it. When I wake up, I look in the garden and I start to rave: "which idiot has chopped my tree while I was asleep? When I now sit in the garden it will be too hot for me since there is no shadow!"
This happens when you see everything always as "new". When you don't see the relation between your actions and their consequenses. This may look highly unreasonable and highly improbable, yet this is exactly what happens in a chess game. Today my opponent made an unexpected knight move. I was in a bad position, and I was looking for eternal check. I looked at the consequences how his knightmove and I concluded that I could still put my rooks where I wanted them. After a few moves I gave a check with my rook. In stead of moving his king away, he simply put his knight in between. I had totally missed that move. I had seen the unexpected knight move. I had seen some consequences, but not all. You may argue that in this case, it was not me but my opponent who made the move. It was not you, but it was your neighbour who chopped the tree. But that doesn't make a difference. Somehow, we are blind for the consequences of actions, when it comes to chess. We see the action, but don't see the consequences.
This, and only this, is the main reason why we are so bad in chess. We see the actions, but are consequence blind.We see everything "as new". As if the consequence is there without a cause. No matter if we were the cause or our opponent.
This is what a brainscan of the amateur reveals. We see always everything as a new position. Every move. No matter if it was your move or your opponents.