The negative publicity leading up to the Rio Olympics fostered a sense of both anticipation and apprehension surrounding the Games. So the organizers and NBC were doubtless relieved to see the opening ceremony mounted without a significant hitch — that is, other than its ponderous pace and bloated duration.
Source: http://rss.cnn.com/~r/rss/money_news_international/~3/QyCz5PHTQLw/index.html