Some years ago, a church I was a member of was praying for revival. God told me a date, and said to quietly watch. The Sunday he had specified came. During the service, God's presence arrived like an express train and was overwhelming.
But pretty much everyone missed it, because they were all looking for signs and wonders.
While those are tools that can help bring about revival, revival springs from relationship. If you don't believe you really have an intimate relationship, if you think you have to do something to win approval (revival, healing, saving your marriage, seeing change in someone, whatever), you aren't likely to experience revival. Not because God doesn't want it, but because you aren't ready.
Inspired by a post by Monty Dickerson quoting Pieter Swart.