I'm having a hard time grasping the concept of lockdown and why it is important. When a hen is sitting on eggs and it comes down to "lockdown time", she doesn't raise the humidity to 70 (or whatever) and obviously in the last 3 days she has to get up and eat/relieve herself..so why is lockdown important? Wouldn't the chicks get shrinkwrapped when she got up and the air reached them? So then why can't I open the bator considering I already have a ton of vents open, what is the difference? Can someone please explain this, as I am confused.