I found it easy to miss important details when practice karate techniques in the air, for example, blocks get too low or strikes miss targets. This happens a lot especially when I'm rusty with my techniques.
One of the ways to keep things on the right track is to imagine an opponent. Imagine when and where he attacks, and thus trying to act on that. Also, imagine how he reacts after you block or strike, imagine what his next step is.
I'm absolutely loving this idea of having imaginative opponent, and very bad at it at this point. I believe it can be learned if I practice while pay attention to forming this habit :)