Cutting is usually without signalling, passing too closely by in the process, thus preventing you from doing what you were about to do. It can result in an accident, and ALWAYS results in the one getting cut off getting varying degrees of road rage.
L’kaf zchus, it IS possible to cut someone off and be unaware that you did so. But only once in a while. If you are cutting someone off inan obvious way, or they, you, it was deliberate, thoughtless, and provocative.