Being a security guard can be fun, exciting, or downright boring. It depends mostly on the assignment.
Though some companies have their own security staff, more often than not, security is hired on a contractual basis. I worked on and off for several years as a contract security guard while pursuing my degree in criminal justice at a local college. Most of the jobs involved asset protection: construction sites, car lots, even the farmers market. This was part of the "bad": Guarding watermelons and potted plants can get fairly monotonous at 3 a.m. The good parts were the occasional concert, carnival, or local community event. These type of assignments usually mean better hours, seeing people -- and every now and then, a free hot dog.