Fame
Have you seen the Secret Service agents trotting alongside the president's vehicle? Or perhaps spotted them scanning the crowd for troublemakers at a presidential appearance? You can't miss these people—monochrome suits or park ranger-style outfits, sunglasses, weird spiral noodle thing coming out of their ear. Do you think for one minute they're trying to become famous? Of course not. They're trying to be seen without being the targets.
Secret Service agents aren't in it to make headlines. In fact, if they get into the newspapers at all, we're going to guess it isn't good news. The good agent is the one who's seen and not heard.