Companies die on average after about 15 years. IBM had a set of core principles that helped it survive, even through tough times like the depression. IBM was known for its excellent management training (ask about the Monkey lecture) and promoting from within.

In 1995, they hired Lou Gerstner (aka the cookie monster) from Nabisco as CEO. He did not share the core principles. My whole department was laid off. It was amusing to have an exit interview (aka getting fired) sitting across from a manager with a sign that said, in essence, IBM doesn't fire. They used to try to contact other managers to find a "better fit" for your skills. Gerstner basically felt that unemployment was a better fit.

After that the company was lost. It has never recovered from Gerstner. It never will.