Many teams are seriously busy to purchase new talented players against next season, but Napoli are not showing any sign of having interest in new players. Maybe their coach is well confident on their players, that they will do better in next season than this season because they have a good midfielders and strikers that made many people to like the team. I guess, Napoli players will going to demonstrate well in next season to make their coach happy again.
I think it's not that they are not interested, but Napoli are not in a hurry to recruit new players considering the squad they currently have is quite good but to add a few players it must also be done in order to prepare a good team to fight for the Scudetto next season.
Currently, the Serie A teams are very aggressive in recruiting new players, considering that last season there were not many teams competing for the title and the big Serie A teams were also very poor last season and now they are improving to be better.