Basic Q about market value vs. selling price

[Jeb Brilliant]

Can someone explain why the market value can be $50k on a house but the asking price is $25k? How is market value double what the actual value someone pays for it is? 

I assume I'm just naive but this does t make sense to me. 

[Rodney Kuhl]

@Jeb Brilliant Don't go by the values on Zillow. They are way off here in Indy.