Rule 1. If current speaker selects next speaker then that speaker is expected to take the next turn.
Sometimes while speaking we select the next person to take the turn, this may be done in a variety of ways, such as naming directly:
Text 3 Wiggins (2002: 319)
Or non-verbally by looking at the person:
Video 1 – Eric Laurier (2011)
At line 4 having been addressed as a group, selecting both customers as next speaker, customer 1 self-selects and then uses her shift of gaze to select customer 2 as next speaker. At line 5 customer 2 takes the turn to confirm they will pay separately.
When someone has been selected it is expected that they will take their turn at the next transition relevance place, as Simon does in Text 3, though, as we see shall later, this does not always happen.