Proverbs 28:19 (NIV)
He who works his land will have abundant food, but the one who chases fantasies will have his fill of poverty.
I have chased my fair share of fantasies. None of them turned out. I have followed a few dreams. Some of them have worked out better than my wildest imagination. What is it about chasing a fantasy that is different from following a dream? Chasing sounds hurried, unplanned. Fantasy sounds unreal. God speaks in dreams all through the bible. But he does not speak in fantasies.
You can follow a dream and it may take years of thinking and planning, trial and error, small calculated steps. And let's not forget much prayer and seeking of council.
When you chase a fantasy, none of these things apply.