Why don't we "get" everything we want? Because we don't deserve everything that we want. God promises to give us everything we "need", not everything we "want". And why don't we "have" everything we think we need? Because we often think we need things but those things aren't necessarily used for "good work". God will provide what we "need" if He feels we will use it for good work.
Lord, thank you for providing, now let me provide You with good reasons to provide for me.