When selecting talent, you can't go by seniority — you have to look at real ability.
Tips
usage
Almost always negative — criticizes a system that rewards tenure over merit. The natural opposite is 任人唯贤 (appoint by merit). Common in discussions of workplace culture, especially in older Chinese state enterprises.
memory
资 = seniority/qualifications; 辈 = generation/cohort. Together: ranking purely by 'how long' and 'which generation,' not 'how good.'