Is there ever a reason to fire a high-performing employee?

Yes if you have receipts of misconduct

Yes. If they steal or are involved in acts of immorality

To answer a question with a question, why would you fire a high-performing employee unless he or she has emotional or personal behavioral issues. Some high performers do have behavioral issues. In making a decision to fire a person like this, would require personal counseling. If that does not work, then there would be reasons to fire a high-performing employee.

if they are negatively impacting everyone else

Depends. Is their “high-performance” consistent? How’s their attendance? Are they a good employee otherwise? Do they contribute positively to the team and are they helpful with other employees who are maybe struggling? Do they cost too much to keep around? There are many things to consider.

Absolutely! In fact, high performing employees are often disruptive and, if reasonable accommodations can't be made to shield other valuable employees from this often toxic output, Icarus must crash. It can be the best thing for the high performer, too. I know that it was for me. I started my own company after being "let go" (heck, they hired an armed guard for three months after I left, thinking I was the type to take revenge) and within six months I was in the black. They tried to rehire me at twice the salary, but I was making 10-fold that so I declined.

Yes. If the employee is high performing they could still be fired for failing drug tests, refusing to comply with testing, failure to supply incident reports for major injuries and such. Repeat incidences of insubordination, harassment or leaving during lunch/breaks can be sufficient for firing.

Theft trust issue harassment lying I can go on