When things start to go bad, the people with the most options on the outside leave first. That leaves the good people who see the problems but think they can help fix them. Eventually those people get burned out when the change doesn't materialize and they start leaving. Eventually all the good people who are left get burnt out trying to do more with less, so they leave too.
That leaves two groups remaining. The first is the true believers - the people that got us into this mess. The second is the hostages - people with no options outside or those treading water until 55.