There is a concept that is foundational in the thinking of the greatest martial artists, spies, athletes, security professionals and criminals (as well as several other key occupations). I'm not saying I would ever become a criminal, but I'm also not saying it would be a bad thing to understand their thinking. If a person can think like a criminal, they can protect themselves and the organizations or people they work for.. not to mention their own families from becoming the victims of a criminal act. But it might help to focus on the other occupations, just because.
Make sense yet? How about an example: a Russian spy working in the United States is walking home from his cover job on an average day. He turns a corner and notices that a man in a black suite is carrying an M9 handgun in a shoulder holster. If the spy was not able to differentiate between an M9 and a Beretta 92 (something I must admit I would have no clue how to do), there could be some severe consequences... the M9 is military issue and the Beretta 92 is not. That piece of information could be key in identifying the man and remembering the face.
Know of any good ways to become aware of specific things? What things are you more aware of than the average person might be?