I have found that the females prefer having the peat moss packed in tightly. They feel much more secure, apparently, when they can burrow in and make their own little nesting area. When you have it too loose, they will prowl around for a long time looking for a better place to lay the eggs. I think the females are looking for a place safe from predators too, so it would make sense they wouldn't want to lay them in a place that would be too easy for a predator to find them.