Look at the St. Louis Rams, the defending Super Bowl champions who barely made the NFL playoffs last year and then were knocked out in the first round.
Success can cause overconfidence, a focus on personal rather than team goals, or even arrogance.
Some may think that if past patterns of technique and effort are followed, success will be replicated. Clearly, success can be defined in a number of ways. However, success is not just a good day or a good week. But despite a history of success, people and organizations are evaluated on current performance. It's not necessarily what has been done in the past that counts.