Everybody has their own opinions and trusted ways to hatch,,but with an incubator located in the house,if properly set and monitored,,about the only,ONLY reason a good hatch wouldn't occur is if the power goes out for 4-5 hours.Even then if at home,I have set a lit candle inside and then watched a digital thermometer to monitor the heat inside.To me this cuts out many enviornmental variables involved with using broody hens,peafowl,ect,,no predators to worry about,,no hens deciding they no longer want to set because of several factors that can happen,,no broken eggs,nests disturbed by another hen,,inclimate weather if she's setting someplace outside,,the list goes on and on.