The logical corollary is that //any senior staff members //who have been in their job for an extended period //are incompetent.
【主干】 The logical corollary is that+表语从句， any senior staff members who have been in their job for an extended period are incompetent是表语从句。表语从句中套了一个从句。
【修饰成分】who have been in their job for an extended period 是定语从句， 修饰 senior staff members。
【翻译】合乎逻辑的推论是： 任何在其岗位上任职时间过长的高级员工都不称职。
