Indicators of non-performance
There are a few indicators that a pair is not performing well:
Disengagement may present as one of the members physically withdraws away from the keyboard, accesses email, or even falls asleep.
The "Watch the Master" phenomenon can arise if one member is more experienced than the other.(Expert-Novice) In this situation, the junior member may take the observer role, deferring to the senior member of the pair for the majority of coding activity. This can easily lead to disengagement.
Silence immediately indicates a lack of collaboration.