How do you discuss non-functional requirements without sounding rehearsed?

When discussing non-functional requirements (NFRs) like availability, latency, and consistency in system design interviews, I sometimes feel like I'm just listing them out robotically. It's hard to weave them naturally into the conversation without sounding rehearsed or like I'm ticking boxes. How do you approach this? Do you ask about specific NFRs upfront, or do you assume certain ones based on the problem statement and then clarify? For example, if designing an e-commerce platform, do you immediately jump to 99.99% availability and low latency, or do you frame it as a question to the interviewer? I'm looking for ways to make this part of the discussion more organic and less like a checklist recitation.