Why do security guards follow people?

Anonymous
I don't think I look suspicious or anything, I've never stolen anything. I don't get why, but it has already happened to me. Like today, I was shopping with my mother and noticed this security guard staring at me, he followed me around the store, staring again. I thought it maybe had nothing to do with his job but I wasn't wearing anything revealing. Last time I have also been followed by one, he also talked to another one watching me until I left the store.
What kind of people security guards follow exactly and how can I do to prevent it from happening again? I'm 17
Why do security guards follow people?
9 Opinion