Is it because you have to wait for an external cue to start your sentences? I recently had an experience where I had a whole SMS conversation with my wife (4-5

Is it because you have to wait for an external cue to start your sentences? I recently had an experience where I had a whole SMS conversation with my wife (4-5 back and forth messages) without typing. And the thing that was jarring to me is that I had to press a button, wait for an interface cue, and then talk. All that waiting for external stimulus would often mess with my natural rhythm to speak.