It only takes 2 seconds to be late on reacting to an attack. Most times that means you lose and will probably die.
A cop is killed on the job every 36 hours.
If you are approached and start to act stupid you become a candidate for deadly force.
This is what cops get for being caught by surprise or late on the draw.
These are just four incidents of the many documented cop killings. So just know that you are playing a high stakes games with you decided to resist or do something stupid. They can't afford to give you the benefit of doubt. They are afraid and ready for whatever may come.