You would assume that any competent manager would always hire the most qualified and experienced person for the job. But I have often observed that even very good managers sometimes “hire down” as opposed to “hire up”. They pick a minimally-qualified applicant over much better candidates. Perhaps it is sometimes subconscious – they inately fear choosing a candidate that might be able to replace them. Or it is more indicative of a need to control – a weaker employee is easier to control.
In any case, it is bad for the organization, and ultimately bad for the manager. A great manager does not fear hiring someone more talented than they are. They realize it will make their life easier, improve performance for the organization, reflect well on them with upper management (unless they are so completely incompetent that they need to go anyway), and ultimately will allow them to move up in the company.
Great managers always hire with an eye towards finding a candidate that can replace them – so they can elevate to new heights in the company, knowing they have a hand-picked talented team to support them.