The most common reason (anecdotally) is when most or all of the panel feels that the officer in question has been able to handle a significant stretch in their jobscope.. stretches into the area(s) that are relevant to their desired career track, while still maintaining standards in their bread and butter work (T&L and Student Devt).

Granted it is quite subjective, and it's quite dependent on whether the work is visible enough to everyone on the panel. Being 'strategically deployed' across different committees headed by different KPs is one way to increase visibility. But this also means.. a lot of committees lor.