If someone has an issue they need to discuss, shouldn't they talk about this issue from the start rather than bring this up later unexpectedly?

As a physician: It is my preference. All too many times, someone spends a full session discussing whatever, & then waits until they are walking out the door to disclose what was really bothering them. This insures that either we don't get to address it (so it is their form of avoidance) or if i bring them back into the office to address it further (that it will cause appointments to be late for the patients who.