This disregards the effect of inertia. Looking for a job is a lot of extra work that must be undertaken in the context of already having a job - working around

This disregards the effect of inertia. Looking for a job is a lot of extra work that must be undertaken in the context of already having a job - working around schedules, interviewing etc. It is simply easier to continue working at the same job, so I don't think you can say "they would have obviously quit if there were better opportunities." Edit: sp