>Over ten companies in 20 years is a sad resume that calls into question either his ability to seek out meaningful employment or some other issue with the author, like terminal "grass is greener" syndrome.

Changing jobs is what does work long term for them. In any proffession, why do you have to be at the same place for years upon years? In the tech industry, you will rarely get paid more, learn more, or really 'move up' if you stay.