I agree that changing the coach does not guarantee that the problem will be solved, as happened to Chelsea some time ago for example. But the hope to bring change is also there, this will actually be a very difficult consideration for them. If they are wrong in appointing a new coach, then it will be a disaster and the problem will become more complicated, but if they appoint the right coach, then it will be a good solution.
But I would like to say that a change of coach is not guaranteed to bring about a change for the better, but it could happen.
Football comes with different options and hopes for us to have. Using the illustration of what happen to Chelsea, they suffered big time before finally settling down to increase their levels of football. However Bundesliga is different, they don't easily sack coach, rather they're keen on becoming reluctant when it comes to relieving a coach off his duties. A coach can either be the reason why a club is declining in performance and can also be the core reason behind the upgrade level of a club, the probabilities of this to happen is 50/50 chances.