It is true that managers of football clubs are often the most highly-criticized people on the pitch, while they are not often praised for their efforts and hard work, which goes unnoticed.
Clubs can go through managers like water, continually trying to improve themselves. Think of Inter Milan at the beginning of the season, from Leonardo to Gasperini until finally deciding on Claudio Ranieri. Meanwhile, during Arsene Wenger's 15-year reign over Arsenal, Real Madrid have had 14 different coaches.
Most European leagues have finally gotten back underway after the winter break, which, of course, includes the top four leagues in UEFA—according to the coefficient ranking system.
Now, looking back at how the season has gone so far, here is one manager from the each of the "Big Four" who has done the job the best so far.