How to plug the sinking ship

Are there common things you have seen happen that make a ship sink fast in terms of the quality of their software? What about common things orgs try to fix that don't actually solve the problem for customers? What happens when companies start to trend downward, lose customers, and the attitude begins to turn sour? Do you just jump ship. And if you don't, what sorts of problems do you look to first to solve the overall quality issue of software at your organization? Are there actually documented cases of companies trying to fix the problems and it just not fixing things and then they learned their lesson and posted what they should have done?