I will complain if we don't win the league, but this season will still be underwhelming irrespective of whether we win Serie A or not. We were supposed to build on what we accomplished last season, and elimination at the group stage in Europe is simply unacceptable. Hence, we didn't improve. Thus, the season is a failure.
Let's say you get 93% on your exam, and the following year you score 88% on the same subject. By definition you haven't failed (as 88% is still a good score), but given your high standards you have inevitably failed, as in essence you failed to improve.