Final answer:
The number-one reason a client may change veterinarians after the euthanasia of their pet is lack of empathy.
Step-by-step explanation:
The number-one reason a client may change veterinarians after the euthanasia of their pet is lack of empathy. When a client undergoes the difficult process of euthanizing their beloved pet, they expect the veterinarian to be empathetic and understanding. If the veterinarian fails to show empathy, the client may feel mistreated and choose to switch to another veterinarian. This emphasizes the importance of empathy in the veterinary profession.