MJ was one of the greatest, probably the greatest ever basketball player ever lived, but he is definitely not a good owner at all by the looks of how the team has done since he took over.
It's worth noting that the Hornets have always been the underdog, even when Jordan wasn't the owner and the team was called the Bobcats. They've never won a championship, a conference, and a division. Besides, they've only reached the playoffs 3 times in the last 18 years. So even if Jordan really wants to improve the Hornets' results, he will need to invest a lot more money and time.