The problem is that the nest group is hyperaggressive and can't be set to "don't fight" which means once the battle gets close to the queen (happens quite often because in most levels the queen is literally sitting next to the entrance) the workers will charge the enemy and die instead of placing eggs.Mike said:Workers have to repopulate the tiles with fresh eggs to grow into new soldiers. If your workers are preoccupied, dead or on a trail far away from the queen and nest chambers you won't get new ants hatching.
This is why it's always a good idea to keep a group of workers in the nest group (the leftmost one). If they're in that group they will pick up egg jobs as they appear.