Others experienced rapid growth, but eventually fell to corruption later on if they were not able to resist the dark impulses within them as they gained more power.
There did exist Spirits that had a much greater willpower that let them hold onto their state as a Spirit, but not all of them were able to possess such qualities, which would end up resulting in them giving in to the corruption and becoming an Evil Spirit.
If they were left to grow in a safe environment, then there would be little to stop them from growing to reach their fullest potential.
There was a period of time that Ash would have to check on the boxes that contained those that she did not use immediately, so that she could monitor their growth.
She released them into a circle where it would be contained, while it would be checked to see if it was reaching a size that would be difficult to contain in its current container.
