Guys often see a pretty woman as already taken.

He is already assuming that you have a boyfriend, and as a result he chooses not to approach or ask you out.

Since you are pretty and have been consistently told so by people throughout your life, he knows you are aware of how attractive you are.

As a result, he believes that you will have criteria for what you like or find attractive in a potential mate.

After assuming that you already have a boyfriend upon seeing you, he is thinking that he would never match what it is you would find attractive in said mate.

Whatever insecurities he has about his physical looks come to the forefront of his thoughts.

He is thinking about his mundane hair, eyes, jawline, nose, etc.

Everything about his face that he has always been self-conscious of comes to the forefront of his thoughts.

He remembers his school days and how he was frequently made fun of based on some part of his physicality.

All of these insults had a powerful effect on him as a youngster and were formidable in shaping how he sees himself as an adult.

When he sees your pretty face, he instantly assumes you never had to go through anything like that growing up.

If anything, you were constantly given compliments from everyone at school, including the janitor.

Additionally, he remembers what girls who look like you typically dated when he was in school.

The tall, dark, and handsome type.

He doesn’t deem himself matching such criteria.

He could be tall enough, but his face doesn’t have the features he remembers of those guys who got to date the pretty girls in school.

Thus, yet again, he disqualifies himself from talking to you and subsequently asking you out.

The reality is, on many an occasion, a guy who sees you consciously disqualifies himself.

This is where he immediately runs through a list of reasons why he would be unqualified to talk to you and ask you out.

So far, he has assumed that you already have a boyfriend and that his physical looks and features don’t match the criteria you look for in what you would be attracted to in a potential mate.

Additionally, he is observing your body language, and it is uninviting.

As you avoid eye contact, scowl, cross your hands over your chest, maintain a physical distance, obsess over what you are scrolling on via your smartphone, hurriedly rush somewhere, and not make polite conversation with any strangers around you, he assumes that you don’t want to be approached.

Since guys are tasked with having to make the approach if they see a woman they like, they are enormously fearful of rejection.

A guy who is thinking about approaching or talking to a woman he finds attractive does everything in his power to mitigate the risk of getting rejected.

He looks to positive body language cues such as a smile, eye contact, close physical proximity, mimicking, and a leisurely pace as strong signs you are open to being approached and talked to.

Without these positive body language cues, he airs on the side of caution by not talking to you and subsequently asking you out.