Business & farm

Same thing happened to me: started return from business using the wizard, while adding income the refund grew bigger, then for each expense I put, the refund shrunk.  Happened last year as well.  I am just perplexed as to why.  I read elsewhere that it may be due to EIC calculations in the background; still, AFAIK, the less you earn the higher the refund so that would not intuitively explain why expenses reduce it.  Has anyone figured this out?  Perhaps somebody from TurboTax can help clarifying?