Describes someone or something that continually achieves desired outcomes without fail. His unfailing efforts finally resulted in a well-deserved promotion.
Pro Tip 2/3
Not Infallible
While 'unfailing' implies consistency, it doesn't mean incapable of error - context indicates limitation. Her expertise seemed unfailing until the new technology proved challenging.
Pro Tip 3/3
Beyond Skills
'Unfailing' often extends to describe character traits that contribute to reliability. His unfailing honesty makes him a trustworthy leader.