The Raiders are the opposite of a winning franchise. Not because they tend to lose most of their games, but because their M.O. is the opposite of winning teams like Indianapolis or, as much as I hate them, New England. Those teams have a system where the things that work for the organization are nurtured and allowed to thrive, and the things that don't work are ironed out and disposed of. The Raiders have a system where the things that work for the organization are left out to fester until they're no longer useful, and the things that don't work are allowed to grow like a cancer, sapping the energy out of the positives of the team.
The first thing they need to do is to fire that asshole owner of theirs. Al Davis is the source of their problems. He rules over the team like a godfather over the family. He thinks that intimidation is a good way of getting respect from the league, the players, and the fans. Too bad for him his team's in Oakland, and it takes A LOT more to intimidate someone from Oakland than an asshole team owner with no loyalty to the city.
He mismanages the team by not hiring someone competent to make decisions. Don't think that's true? I've got two words for you: JaMarcus Russel. Yeah, so he looked like the quarterback of the future for the team, but when he proved to be otherwise he should've been replaced by someone who could get the job done. Instead, they kept him in, and built his legacy as a dud. It's so obvious to the fans that they actually paid for a billboard that says, "Mr. Davis, the fans have one thing to ask from you: hire a GM." just up 880 from the Coliseum.
Another reason why they're the opposite of a winning team is the perception of the players in the community. Other teams' players, with a few exceptions, are role models for the community, getting involved in youth programs and community activities. The Raiders, though, don't seem to hire anyone who doesn't have a criminal background.
Lastly, and this one doesn't have to do with the team itself, but is part of the reason why the Raiders are disliked, are the fans. Just like the players, it seems like being an ex convict is a prerequisite for being a fan. They wonder why their games never sell out and are always blacked out on local networks. Well, when you intimidate other teams' fans your games aren't gonna sell out. I read a statistic once about how normally 25% of the crowd is made up of fans of the visiting team, but, due to intimidation from the fans, a normal crowd at the Coliseum is only 10% visiting team fans. Maybe with the missing 15% they'd be able to sell out their games and not have them blacked out. I know I'd never go to the Coliseum to watch the Dolphins just for fear of not getting out alive. I was told once by someone who was at a game against the Broncos how after the game, which the Raiders naturally lost, there was a man wearing a Broncos hat walking out of the stadium with his family. Suddenly, out of the crowd someone punched the man in the face, and 3 people kicked the shit out of him while he was on the ground. And they wonder why other teams' fans are afraid to go to Raiders games.