Because God is allowing the Israelites to suffer and be impoverished, Gideon believes that the trouble is being caused by God.
This is wrong, because the Israelites had "done evil in the eyes of the Lord"; they are responsible for what has happened to them. The circumstances they are in are because of their turning from God --- if they call upon the Lord and submit to him totally, they will be removed from these circumstances and restored.
People who rely simply on themselves usually end up on the short end of the stick, because without the guidance and leadership of God we are too weak to take care of ourselves and whatever circumstances that we are in. If we relinquish our will and depend on the Lord, he will make us "mighty warriors" and we can overcome the circumstances that we are in.
In all things we must put God first and have total reliance upon him ... he knows what we need and why we need it ... even though what we want is not what he wants for us.