Not necessarily 'mismanagement' in the sense of somebody being at fault. Just pieces not fitting into a particular puzzle that a club has at a given time. Our team developed in a way that didn't suit Fernando all that well. A real shame, don't forget the guy publicly announced he was coming here on a free transfer and got ostracised from his team and basically his community for it.
Mismanagement for me is more like when players get bought who don't fit the direction the coach wants to go in (which would be a failure of upper management, the SD buying players without consulting the coach), or when big players go to new teams and fail to click (Shevchenko to Chelsea for example, how can you ruin a CF like that?), or when players fit the coach's system exactly on paper and fail to do well at their new team. That goes down to bad management by the coach.