Day 22 no one has hatched

[scny]

Today's day 22, my chicken has been setting on them and not one has hatched( 8eggs). She's a free ranged chicken so she's outside and 2 weeks ago it rained a lot, so I was wondering if that's why no chicks have hatched. Help someone?

 

[Nocila]

Some hens are better brooders than others, I have some hens that switch nests a lot, some who barely leave the nest for anything, and others who seem to forget about their eggs when they are off the nest. It could be any number of things. Have you tried candling the eggs to make sure the eggs were fertile?

Also, I hear that, if the eggs cool for a bit after the 10th day or so, then the hatching date might get bumped back a bit, so maybe that has something to do with it?