Could well be.
When you are a Chelsea manager, you know that the expected length of your reign is 12 months. Would you start buying and selling lots of players players and building your own new team if that was your expected tenure? Or would you add finishing touches to the experienced and talented core you already have? Of course you wouldn't want to make massive changes. No point building your own side when you won't be around to bear the fruit of it. As each season passes, those core players (the likes of Terry, Lampard, Drogba, Cech, Essien) become older and regress and pick up more injuries. Hence each new manager fails to achieve the owner's objectives.
No long term thinker, such as the likes of Wenger or Guardiola would even consider taking the job. Instant gratification managers like Mourinho or Hiddink would be the best bet, or some other lower tier manager who has no other top tier options.
In any case, there could be a real manager merry-go-round in the summer. If we miss out on 4th Wenger may leave, Mourinho will likely leave Real Madrid and Inter may want a new manager too given their terrible season. That would be Villas-Boas, Wenger, Mourinho, Benitez, Ranieri all available.
Joachim Low is rumoured to be high on Chelsea's wish list while Harry Redknapp will likely leave Spurs at the end of the season for the England job.
That could then be France, Germany, possibly still England, Chelsea, possibly Arsenal, Real Madrid, Inter, Spurs, all looking for managers, plus generally another few national teams following the Euros.
Gossip mongers will have a field day!