You want your clients to call you, but you never want to force them to call you back. At first, this seems contradictory, but consider it further. To develop a successful practice, you want your clients to call you when they need you. You want them to trust you and to think of you first when they have a need for their animals. You want clients to know that you are there when they need you. You want them to call you.
However, in serving your clients, the intent should be 100% satisfaction. 100% satisfaction is built upon providing service that is complete in every way. It is well-defined in advance. There are no surprises. Their expectations are fulfilled and there is no frustration about failed expectations, difficult or unclear choices, or lack of follow-up. The 100% satisfaction benchmark is a guide for helping to predict what questions clients might have, what challenges they might face while engaging your services, and providing clarity regarding how to get what they want from your services. If you notice that you are receiving a lot of calls from clients seeking the same information or as a result of the same frustration or lack of clarity, that is a signal that you have an opportunity to improve your service so that fewer clients will have to call you to get clarity for something they should have already received.
The goal should be 'never make them call you back'.