Here's why:
* Focus on healing and spiritual guidance: Medicine cats are responsible for the health and well-being of their Clan, both physically and spiritually. They need to be fully dedicated to their duties and can't be distracted by the demands of a mate.
* Maintaining neutrality: Medicine cats act as mediators and peacemakers within the Clan, and often have to deal with conflicts between different cats. Having a mate could lead to bias and compromise their neutrality.
* Avoiding power struggles: A medicine cat's mate could potentially become a rival for power or influence within the Clan, disrupting the delicate balance of leadership.
* Protecting the sacredness of their role: The role of medicine cat is seen as sacred and linked to the spirit world. Having a mate could be seen as a distraction from this important spiritual connection.
Exceptions:
While it's strictly forbidden, there have been a few rare exceptions to this rule in the Warriors series. For example, StarClan has occasionally allowed medicine cats to have mates in times of great need.
Ultimately, the decision to remain single is a conscious choice made by medicine cats, ensuring that they can fully dedicate themselves to the well-being of their Clan.