Praying Beforehand

SimchaMinute by Rabbi Avigdor Miller 

As to why praying to Hashem beforehand is more effective than praying after the person is already in the midst of the problem, the answer is that praying beforehand when the person is still well demonstrates his trust in Hashem... When a rich man prays to Hashem to give him his daily bread, Hashem is pleased. When a poor man cries out, that’s also good, but there much less of a reward... — Ohr Avigdor Shaar Bitachon