I used to worry so much about following the directions exactly to how the incubators called for, and was constantly searching and reading in this forum about every step of every day of the incubation.
Then I had my first hen go broody. I was so worried when the eggs were exposed while she left. LOL. They were exposed to very hot weather and very cold weather (have had several broody's now. And mother nature takes care of those chicks during those 19-23 days.