God gives us hardships in life so that we people will seek his help, God is just trying to know who among us is the right one to go in his home in heaven. Praying is not actually a waste of time, research says that praying is actually good for health, it's like counseling but instead of saying your problems to the counselor you say it God.
They pray because they believe in God. This is the sign that we love and owe him. We pray to guide us in every moment and every second in our daily activities in every day. We pray him to thanks for what have he done to us for good. We pray him to forgive our daily sin eventhough we do it again and again but he cant tired to forvgive us thats why we owed him and we believe.