Because attitude is the interpretation of life as it comes at you. Your senses pick up signals about the world around. Your brain has to listen to the things that people do to you, for you, and sometimes against you. Their words and actions are life coming at you. All those words and actions have to go through your attitude to get to the other part of your brain that controls your mood and your reaction. Two different people can ingest the same set of words and react to them differently because of the internal attitude.
Sometimes you cannot control all that outside crap that you must ingest. But the attitude is the ONE filter that you can always control. It is the only thing that matters when it comes to happiness, sadness, joy, and pain. Sometimes that attitude can get the crap beat out of it too. After so much sadness and pain the attitude has to just take a break. F that happy crap. I deserve to be a little pissy for a while. But it should eventually recover and be stronger on the other side.
If you have a pissy attitude, ride it out and get over it. It won’t get you anywhere. If you have a great attitude, then the world is yours for the taking.
Try to have a great attitude today.