Loyalty is often an underrated attribute. It's important for large networks to be oiled by trust and having everyone work from the same page will mean that things actually get done. The Bush family values loyalty highly - it's a theme prevalent in 41, George W's book about his father. A recent NYT article covering Jeb Bush's campaign and their insistence that policy advisers only advise his team highlights how he has similar views on loyalty.
One of the major problems in politics today is a modern elite patronage system in which the government enables the continuation of rent seeking opportunities to large political donors. In this environment, an overvaluation towards the concept of loyalty can backfire. Loyalty to people will mean loyalty to insiders who have been benefiting from policies at the expense of the public.
Jeb Bush comes across as one of the more outwardly sensible GOP figures when it comes to policy, but libertarian leaning supporters need to remember that someone who values loyalty highly will have little interest in dismantling the system that has served their supporters well for decades.
The principle applies to more than just one family, but it's helpful to remember that seemingly good qualities can have significant drawbacks in the wrong scenario. It's also an important reminder that it is important to identify the long time supporters of politicians, since those are the ones who might be able to call on loyalty for favors that help them at the expense of the public.