HOAs can be capricious. A good one can go bad easily. All it often takes is one motivated individual selling their unit and leaving the board and the rest fall to bad practices with a newly motivated member pushing some agenda.
You also have two layer of complicity to deal with. There is the HOA board and the Property Management agency.
The PM’s job isn’t to get the community the best deal. Their job is to show reasonable diligence in executing the boards directives. Hence, they have stables of preferred vendors whose qualifications are often the working relationship.
As for the boards, conflicts of interest are so common it should be assumed.