Prayer obtains what it is due to obtain — not what I personally want to obtain, which is different. It is useful that islands of prayer exist in the world, even if they are composed of only one person, or two, or three, or four.
We cannot expect answers from God after only five minutes of silence... Meister Eckhart emphasized the importance of the listening heart that listens to God alone ... that God desires nothing more than a heart that detaches itself in silence from everything and turns and listens.