I think it is an above all financial problem, since they spent several money in changing various coaches: i remember paying the salary of those who fire. Now he is missing liquidated to buy and strengthen the team with players who serve and consequently this is reflected on the quality of the game, i assume using the logic, and i am not a great football expert.
Jose Mourinho was one of their recent managers but even he didn't get that much of a money in his salary actually. As far as I can remember, he accepted a pay cut to get only 3.5 million pounds a year. Currently there are so many players making more money than his salary in those times. But their financial condition isn't in great shape that's for sure. As far as I know they are still in debt like around 500 million euros. That's too much...
I hope someday we can see Roma shining again. They can't win a Serie A title since 2000/01 season. They have 3 league titles in their history too. I would like to see them finishing their longing just as Napoli have.