My incubator restores temperature and humidity quickly, as well. So much so that my husband suggested I candle the eggs every day. I told him that I was trying not to because I am new to incubating, and I was following the advice of others, who have more experience than I do. I did experiment with half of my eggs being washed and half unwashed with any debris removed. The washed eggs started to develop, but they never hatched. Well, one did, but that one died. These were guinea keets, not chickens. I did get 17 keets out of incubation so 4 of my unwashed eggs did not hatch. Those happened to be eggs that sat longer prior to incubation. The rest of the eggs had two that were infertile, and there were 12 washed eggs that did not hatch. It is a learning process.
Do not wash your eggs before incubating them. It washes off the protective 'bloom' on them. When you candle or handle the eggs make sure to wash and dry your hands first. Just think about how often a chicken gets off her eggs to go eat and poop, and you can't tell me their environment is sterile, so don't over worry so much! I don't candle every day, maybe once at day 5, once at day 10, then at lockdown....day 18.