It depends on what position they are applying for, as well as the specific company. One of the more common reasons for a senior employee changing jobs is losing the previous one. This includes losing the job to downsizing or similar culling in which poorer performers are generally more likely to be laid off than top performers, with a similar skill set. These poorer performers who often do not give “the best” answers in interviews still generally manage to find jobs at other companies in the industry, including poorer performers with 20+ years experience. Other factors that could be especially relevant to these hires include things like applying for a standard experienced engineer type position rather than a high level principal engineer position (lower salary), networking, and having unique experience and/or skill set.