So true, Richard. My very first ever egg I incubated pipped a day early and zipped out in 15 minutes, spoiling me from the get-go, LOL. Usually, I allow them to take their time, but I have had a couple of instances lately with one hen's eggs in particular, where I had a fully formed, yolk-absorbed, beautiful chick crammed in so tight, it couldn't pip. Two died in two different incubations and the last one had just expired apparently right before we decided to go in after it at the end of Day 21. It simply ran out of air, we think. The next one of her chicks we incubated, we went in earlier and pipped the aircell on D-Day so it could at least breathe and it worked out well. BUT, we are pretty sure what the deal is with her chicks and wouldn't usually do that until we gave it a day or so to get out on its own.