THAT IS a LOT of very useful information!
A lot of y'all seem to have problems with chicks not gettin out. Over the years, I've help like A LOT of chicks out. Some live, some die. I have grown to notice the signs of an egg that needs help and is ready to come out.
Good sighns:
Chick has started zipping but has stopped and is stuck. It's usually ALWAYS ready to hatch.
Chick makes what I call 'happy noises' when you talk to it, tap, or hold the egg. Like when you pick up a healthy chick from the brooder. Those sounds.
Chick has DRY feathers sticking out nesr the hole and tries to struggle out.
Egg has been piped over 12 hours.
Peel a bit of shell of toward the bottom of the egg and poke several little holes into the membrane, if it bleeds quite a bit, leave it for 2 hours and come back to it later.
Bad sighns:
If the chick screams like it's in pain and doesn't make many sounds(no good sounds anyways) leave it.
If there is a LOT of blood and the membrane is reeeeally squishy and doesn't look a bit dry, leave it and wait a few hours.
If the chick sems really weak, leave it, it'll probably die.
I can think up a few more sighns, because I've helped more often than not and I admittedly hve killed some, but I have saved many more that would've died anyways. It's always a gamble with helping chicks out of their eggs, but if u leave them it's an 80-90% chance they'll die.
And also, if the chick doesn't absorb all of its yolk, 70% chance of death. If it lives long enough to dry off then put it in a secluded brooder and wait a few days. I had several(3) quail in december do that. About 15% of the yolk wasn't absorbed. They all lived. And I also had to help out a few too, bc my humidty was low and there was only a couple eggs in the bator so I could pay attention to what happened.
'Nother quick tip: if you have more than 12 eggs left in the bator, lay off unless you can constantly monitor it.
You must always think what's best: the single bird, or the whole hatch? And as far as you know, he chick may not be stuck... it could be resting.
hope I helped someone with this bit of info, for I have defied my grandmas tips on stay outta the bator. Only ONCE in my life have I done a 100% lockdown and it was for 2 days.
I go by the win win, loose loose thing... or is it the ... no pain, no gain? Definately the second~! I apologize for the horrid spelling mistakes, bit I'm dead tired and have algebra homework... that I may or may not do...
P.s! I've lost more NOT helping them than I have helping them. Whadda ya think momma hen does? The help their babes by steping on eggs and eating the shell off(I'm weird, I've seen a couple do it).
P.s.s! If your a newb and can't tell the tell-tale signs, learn from practice and others' mistakes bc I had no one to tell me anything at all about incubation. My very first hatch I had 1 male duck hatch outta a double-stacked incubator in my closet. And I sat for 3 hours helping HIM out

good-luck, and if anyone has issues there's 100,000 other byc-ers at your hand and foot~ use them!