"...When bullying/mobbing occurs, it tends to be long-standing. McKay et al. (2008) found that 21% of their sample reported bullying that had persisted for more than five years in duration. In our 2008 study, 32% of the overall sample (faculty, staff, administrators, etc.) reported bullying lasting for more than three years. This percentage increased to 49% when we focused on faculty.
It may be that academia is a particularly vulnerable setting for such persistent aggression as a result of tenure, which has faculty and some staff in very long-term relationships with one another. Both conflict (Holton, 1998) and aggression (Jawahar, 2002) research note that the longer and more interactive the relationship, the greater the opportunity for conflict and potential for aggression.
Further, while ensuring a “job for life,” tenure may also restrict mobility so that once a situation goes bad, there are few options for leaving. Zapf and Gross (2001) observed that the number of actors was linked to the duration of bullying. They found that the more people who joined in the situation, the longer it went on, concluding that it may become increasingly difficult for witnesses/bystanders to remain neutral as bullying proceeds and intensifies.
Given the preceding discussion, once bullying begins, and the longer it is permitted to continue, the more likely it is that other colleagues will be drawn into the situation—possibly accounting for the higher incidence of rates of mobbing among faculty (Westhues, 2006)...
From: https://provost.baruch.cuny.edu/wp-content/uploads/sites/5/2019/08/Keashly-and-Neuman-Bullying-in-Higher-Ed-2010.pdf