When fans take a step back and look at South Park, they see a litany of absurd characters who are arguably some of the most morally bankrupt individuals on TV. This includes the kids, many of whom are the absolute worst of the worst, but not all of these characters started off as terrible people. In fact, some of them have fallen pretty far over the years, and no one has fallen further than Randy Marsh.
The son of Marvin and Grandma Marsh, Randy appeared quite early in Season 1, when a volcano erupted. As a geologist, Randy was the exact type of person who would be looking into this kind of situation. Back in those days, he was depicted as a family man who just wanted to do right by his kids. That being said, Stan was still often annoyed by him, but that was just typical father/son stuff.
During this era of Randy, he was barely a background player in the series. The stories focused primarily on the kids, much in the same way early seasons of The Simpsons were more focused on Bart. However, Randy and Homer Simpson both made their way into the spotlight by becoming progressively weirder and louder. If Randy has two defining qualities, it's that he's the loudest and weirdest guy around South Park.
Over the 24 seasons of the series, Randy has grown into being one of the most wild characters on the show. He has progressively become more erratic and unpredictable, something that has not been helped by his largely untreated addictions to drugs and alcohol. Even worse, the man is utterly addicted to self gratification on a disturbing, Guinness World Record level. Randy makes some of the worst decisions in all of South Park, and that's saying a lot.
Like Homer, the list of jobs Randy has held over the years is absurd and improbable. He's been a Walmart employee, a security guard and even a member of a boy band, and these days, he operates a hemp farm. While it's never been officially stated, it appears that Randy has a Ph.D in Geology, making him a doctor as well, but he has only been called Dr. Marsh once in the entire series by another person.
Even stranger, it was eventually revealed that Randy is actually Lorde, the singer, and he performed all of her biggest hits. While this is bizarre, this is a guy who spent weeks training to fight other dads at Stan's little league games, so anything is possible when it comes to Randy.
While there were signs of his fall coming in the first few seasons, the Season 4 episode "Something You Can Do with Your Finger" showed his real downfall. The way he responded to Stan joining a boy band was absurd, but even more ridiculous was that he eventually joined the group. It was inappropriate on a number of levels, and performing with them at the mall probably wasn't the best idea.
The depths that Randy has sunk to over the years are truly mind boggling, especially when fans go back to the first season or two. The relatively normal version of Randy that existed in those early days is a far cry from the version that torments South Park today. He went from a concerned father of two school aged children to an over exaggerated jerk whose political views and jobs change with the wind.