A lot of young people want to go into EP because they think it's exciting. Then they find out the job is sitting outside someone's house or outside their bedroom outside while the protectee sleeps. Kinda like how most people think being a private investigator is exciting, until they're parked in front of some guy's house who has a bad back, waiting for says to get a picture of him taking out the trash to send to his insurance company.
Heck, even in the USSS, one of the best trained agencies in the world that deal with EP, there's going to be a lot of boring work. For every guy that walks beside the president, there's going to a a guy doing something like sitting alone in a car all night, every night outside the Vice-president's aunt's house.