"How is expecting the worst increase the chances of getting it? Your statement makes zero sense."

I provided you a link that described the concept.

"...individuals perceive what they want to...It is a broad term to identify the behavior all people exhibit..."

It's a simple concept in psychology, certainly covered in a freshman level psych class. I'm not inclined to waste time trying to educate you. There are probably thousands of web pages you can use to help you with your confusion.