Who says it's just a matter of management? If you ask me, the real problem is that for years they won almost by inertia, with a solid defense and taking few risks, but without that competitive fire you need when the others start breathing down your neck. Inter and Napoli built hungrier squads, and Juve found themselves chasing without that kind of mentality. Then yeah, sure, their transfer market choices did damage, but it also depends on a club culture that for a while thought it could manage the decline with the usual recipe.