Faith is the most important value in God's kingdom. It is also called the fruit of the spirit.
As a child of God, you must live a life full of faith. This is how you show God that you trust Him. It is how to live a complete and whole Christian life.
Many people find it hard to trust God in their circumstances and this is why you should pray at all times that your faith is full and that you are strengthened in your heart to keep trusting God.
When your faith is failing, pray to God to strengthen your faith. This is also an act of faith.
So, instead of feeling downcast when your faith is weak, take it to the Lord in prayer.