Campaign Season

Why can't TV and radio ads for people running for public office ever be about that person? I don't want to know why I shouldn't vote for Guy A. I want to know why I should vote for you, Guy B. If there are 5 guys, and you tell me not to vote for one because he's _____, you just told me I should vote for 1 of 4; not for you. Why can't people just argue for themselves? It's pretty rediculous. Maybe that's what I should do when I get out of college: be a campaign manager for a Congressman or something. Cause I'm sick of it.