In my experience (as limited as it might be), burnout is a very person thing, usually driven internally by the employee with an out of kilter sense of balance between self-commitment and job performance. Common drivers are broken, centralized processes (e.g. stack ranking) rather than individual managers. Staffing doesn't really help, it just raises the bar, because this is a matter of competition.

In the software world, the sheer focus on compensation is not helpful, especially when some of the larger tech firms promote levels of compensation that nearly all "ordinary" developers could never hope to achieve.