I recently learned about the "traffic light rule" through the Harvard Business Review and think it is a very clever way to envision a conversation and stay on point with your customer. (or anyone for that matter)
The "traffic light rule" suggests that when you have the opportunity to present information or connect with another person, you probably have their attention for about 20 seconds, the length of time a light stays green. During the next 20 seconds of the yellow light phase, they will stay with you if you have managed to captivate their curiosity and provide something substantial to keep them listening to the conversation. When the 40 second mark has passed, (aka, the light turns red), if you still have their attention, you will need to wrap up what you are saying in the next 20 seconds or so or you might be perceived as too self-absorbed and a rambler.
Conversation implies talking between two people or more and everyone should have their moment to shine and get their point across. Keeping the "traffic light rule" in mind will help you to keep statements relevant to the conversation and hopefully in service of the other person, making conversation interesting and beneficial to all.