This video about chicken egg incubation really made me long for the excitement of spring, baby chicks, and an expanding flock! I know, however, that for the next couple of months incubating eggs wouldn't be wise, because of the power shortages we experience each winter around here (and which can do away with even the most successful batch of eggs), and the fact that it would be too cold, windy and rainy for the chicks to be outside once they reach the age of "graduating" out of the brooder.
Some things we do/believe slightly differently from what is mentioned in the video:
1. It is stated that "it's not unusual to lose up to 50% per hatch, depending on quality of eggs, etc." Quality of the eggs is the key here. If you use fertile, fresh eggs, which have no deformities and which have been properly handled (eggs intended for incubation must be turned at least once a day, preferably twice, before they are set into the incubator), and if the conditions inside your incubator are favorable, a 100% success rate isn't anything too far-fetched. Of course, the bigger your batch, the higher your chances of losing at least some eggs - but 95% success rate is not unusual.
Alas, if any of these conditions isn't followed (i.e., the eggs aren't very fresh, haven't been turned, etc), your hatch rate goes down dramatically. We always have very high success rates with eggs from our own flock, because we handle them properly. Alas, too many breeders are very irresponsible when it comes to that, and will sell you hatching eggs that are obviously old and weren't turned at all from the point of being laid. We once had a breeder of Brahmas tell us, with incredible audacity, that "month-old eggs hatch with no problem". Not so; we prefer to set eggs up to a week after they were laid, and of course we turn them twice a day in the meantime.
2. The video didn't mention you should stop turning your eggs on day 18. This is important to allow the chick to settle into hatching position.
3. I always bring the humidity levels in the incubator a little higher in the last days before the hatch - that is, more like 75% than 50-65% during the first 18 days. I know there are a lot of discussions about humidity, but this is what we do, and it works well for us.
4. I never leave a chick in the incubator for a whole day. I transfer them into the brooder (a simple cardboard box with a heating lamp and a thermometer for temperature monitoring) about an hour after hatching. I once used to leave chicks in the incubator longer, and because of the high humidity they just never seemed to dry, so I stopped doing that. Our chick survival rates are very high, in case we are wondering, we hardly lose any - almost never any that seem well and healthy at the moment of hatch, anyway.
So, if you have been wanting to do this, hatch your first batch of chicks this spring! If we do it, you can, too. Instructions for building a simple homemade incubator are here.