If we don't have regular one to one conversations, then we risk talking to each other about mostly urgent and emergent issues, catching each other whenever something goes wrong or needs immediate attention. As a result of this we can become reactive and feel that we are always on the back foot.
Scheduled one to ones shouldn't get in the way of stopping for real emergencies. There will always be times when we need to stop and talk to each other because something unforeseen has happened. Planned one to ones can take the pressure off us in the sense that we are less likely to be communicating in soundbites as things happen and more likely to be organising our communications around a planned schedule.