As a general rule, your job in therapy in to speak. This is difficult for some people, and if this is the case, I'm immediately curious about the reason. Often, people speak more freely as therapy proceeds.
If you have no trouble speaking, I'll wonder if you can be quiet. Time will tell. I'm interested in what you say to me, but also in how you say it to me. Is your speech pressured? Are you reluctant to speak? Do you look to me for guidance? Do you act as if I'm not present?
Silence can be a protective mechanism: "I'm thinking, but maybe it's not safe to let you in on it." It can be an indication that, at the moment, for whatever reason, you have no thoughts. It can also be a perfectly healthy boundary. "I'm going to think on my own for a little bit, and I'll tell you what I come up with." This may contradict the basic rule of therapy - that you do your best to speak freely and without filter - but the contradiction can itself be a sign of health.
The question is always, can you be different ways? Silent sometimes, sometimes talkative? Open and then self-protective? Spontaneous and then thoughtful?
This is not a prescription. I'm not telling you how to be when we meet. I'm just saying that, in my work, I am attentive to how people are, what their capacities for being are. Observations of this sort are very valuable, and they relate to one of our end goals: greater emotional freedom.