Can someone explain this to me. On suprnova almost every coin is mining much lower numbers than whattomine suggests. Except Hush.

BitcoinZ with my 9k sols promising 4500-6000coins a day at 180.000dif, but in reality max 2500. Is suprnova cheating or  whattomine not precise? In this situation i see more profitable earning btc on nicehash and then just buy bitcoinz on exchange.

thanks!