Assumptions are the shark-infested waters that can leave you a little paranoid and feeling like you are drifting alone out in the middle of the ocean.
When dealing with the demands of clients/customers you can choose to base your responses on conjecture or assumptions. Or, you can choose to always be open to giving your client/customer the Experience of caring and understanding by seeking to first understand where they are coming from before you respond.
Option A gives you the high probability of taking a course of action that can damage a relationship. After all you are being driven by assumptions that may be unfounded. Option B gives you the potential to continue evolving your relationship in a healthy and productive way. The only difference is the risk you are willing to take. In many ways the easy way out is to make assumptions.
Constantly seeking ways to engage your clients/customers in an Experience is the road less travelled but provides the greatest rewards. If it was easy everyone would do it and then where would you be?