Sometimes the most effective prayers are the shortest ones. Quality, rather than quantity, develops deeper communion with God.
Matthew 6:7, "But when ye pray, use not vain repetitions, as the heathen [do]: for they think that they shall be heard for their much speaking."
Some of the most effective prayers are the shortest prayers. Jesus said, "Peace, be still," and the wind and the waves ceased (Mark 4:39). He said, "Lazarus, come forth," and Lazarus came back from the dead (John 11:43-44).
Today, there is a new emphasis on the quantity of prayer instead of the quality of prayer. Jesus never advocated long prayers, and there are only a few instances where Jesus prayed long prayers. This is not to say that communion with God is not important. It certainly is, but formal prayer is only one part of our communion with the Lord.
Psalm 5:1-2 uses the words "prayer" and "meditation" interchangeably. Therefore, communing with God through keeping your mind stayed on the things of the Lord is also prayer. There are also times in prayer when we need to be still and know that God is God (Psalm 46:10).
Many times we ask the Lord to speak to us, but He can't get a word in "edge-wise." We're doing all the talking.