Some clubs change managers regularly and most still don't get it right.
Aston Villa has had seven in the past six years and has tumbled from Premier League safety to a Championship relegation battle.
On the other hand, in Roman Abramovich's 14-year watch at Chelsea there have been 12 different managers, though thanks to the billionaire's backing, Jose Mourinho, Guus Hiddink, Carlo Ancelotti, Roberto di Matteo and Rafa Benitez have brought 13 major honors to Stamford Bridge.