Your strongest rep is probably the one you coach least.
It makes sense on paper. The numbers are fine, the doctors like them, and you have three other reps who need you more. So the strong rep gets a quick "keep going" and a field day that feels like a formality.
In my experience, that is how you lose them. Not always to a competitor. Sometimes just to boredom.
Coaching a strong rep is not about correction. It is about stretch.
What I do instead:
Ask what they want next. Senior rep, key accounts, a first step towards managing. The stretch has to match their goal.
Give them a harder account. A hospital, a sceptical specialist, a key account that stalled. Growth comes from harder calls, not more calls.
Let them teach. A session at the cycle meeting, or a day with a new joiner. Nothing deepens a skill faster than explaining it.
Agree the outcome and leave the method to them. Hersey and Blanchard's situational leadership says it well: as a rep's ability and willingness grow, the manager moves from telling towards delegating.
The mistake to avoid is picking on small faults just to have something to say. A strong rep notices, and it costs you their trust.
“Your best reps do not need fixing. They need a bigger hill.”
Lesson 7 of 23 in Step 4: Coaching, with the full guide and a checklist for this week.