Back to Mario topic, how many strikers did we have in recent years not knowing a long goal dry spells, where they have dozens of clear chances and just lack the confidence or final move to push them in the net ?
I can only think of Sturridge to never have had one rarely playing more than 3 games without scoring (but as he's injury prone, those 3 games may often be 5 or 6 played by the club) .
Michael Owen had a spell of a dozen games without scoring in 1999-2000.
Fowler had several long dry spells as well, in 97-98 notably, and when he came back to the club in the 2000s.
Torres spent many games without scoring in 2010-2011, only awakening in december.
N'Gog, while he wasn't quality still scored like 5 or 6 goals in his first 20 appearances, only to spend the next 25 without one.
Suarez while he had a good start in 2010-11, was the king of the woodwork and other close misses in 2011-12, he had the most awful spell of his carreer here needing about 20 clear chances to score one. Remember people here saying he had no goal scoring instinct at that time.
Carroll needless to say wasn't regular either.
Etc...
Main problem of Balotelli is he's having one of the worst spell of his carreer (he had a worst one in his last year at City not scoring one in 15 appearances or so, but he was not a starter there, and out of this one was rather regular if not extremely prolific) just when joining us, generating more doubts than if he had one after 10-15 games like some of his predecessors (including in his own head probably).
Not saying he doesn't need to improve his play, and we don't need to adapt to his strength. But strikers having a bad spell, starting with some unlucky games, and continuing with a lack of confidence that makes them miss complete sitters, is nothing new, be it in football in general or here in particular, and even for players you can't question the efforts or quality.