One technician solves the hardest failures and may produce twice as much as anyone else, but teaches nobody, dismisses weaker technicians, or creates an environment where others stop contributing.
Measure the whole contribution
Individual output is real value. So are knowledge transfer, team capability, safety, communication, and whether other people become stronger or weaker around the person.
A leader who measures only completed work can accidentally reward a single-point dependency.
Make the hidden cost visible
Describe the behavior and its operational consequence. Avoid character labels. The issue is not that the technician is "toxic." The issue may be that junior people stop asking questions, critical knowledge remains concentrated, or the crew cannot function without one person.
Those are reliability risks.
Set a standard worthy of the capability
A high-performing technician should be expected to carry a high standard, not a lower one. If they want influence, lead roles, or recognition as the senior technical person, developing others should become part of what excellence means.
Do not demand that every expert become a formal mentor, but do not accept active damage to the team.
Avoid these traps
- Protecting destructive behavior because output is high.
- Trying to reduce the technician's status instead of broadening their contribution.
- Calling the person toxic instead of describing specific behaviors.
- Pairing junior technicians with them before mentoring behavior is safe and productive.
Useful language
What good looks like
The expert remains technically important while the organization reduces dependency on one individual and makes developmental behavior part of senior contribution.