I think greed is part of it, fear another (fear of losing control), pride (they don't want to admit they are wrong), selfishness (they only think of how things effect them). ("They" being the GB/organization)
Looking from the outside of the borg now, it is so easy to see the very huge shortcomings of it. It is hard to see why everyone can't. I guess that is because the one thing they are very good at is brainwashing tactics. They cover all the bases when they indoctrinate people into the organization.