Prayer is total dependence on God. It's like saying "God I can't do this on my own, I need your help. If you don't help me no one else can help me." That is a picture of how prayer is.
If we pray to God with an alternative in mind we may not receive that which we desire. God Is One who doesn't like to share His glory with anyone else. When we pray to God and still go ahead to seek for other means when God does answer our prayer we may fail to give God the credit and instead give it to someone else.
GOD should be the one who we place all our hope and faith in.
Another important thing we are expected to do when we pray is to believe in God who we are praying to. A prerequisite from receiving from God is believing in Him. When we pray in disbelief it simply shows that we are doubting God or limiting his capability.
Faith is very important in prayer and also in every aspect of our lives because without faith it is impossible to please God. Faith works wonders in ways we cannot fathom or imagine.