When we undoubtedly think we have already won, we are likely to work and head towards failure.
Complacency is a self injecting poison, it weakens and eventually kills abilities and innovative zeal.
Over confidence mostly breeds complacency, which is one of the common and strongest catalyst to failure.
No matter how you are resourced, equipped and prepared, a complacent mind can easily make you fail.
Even if you are the best and you are meeting the worst, expect the best from them.
Complacency weakens, guard against it.