[twblalock]

Sounds like a good explanation for why the tech industry in Silicon Valley is so much bigger than everywhere else, e.g. places like Portland and New York and Boston who theoretically could have just as many qualified workers because of their universities, and also offer a high quality of life.

People move around, including to direct competitors. Tech companies in Silicon Valley need to deal with it because they can't prevent it. As a result, new companies are able to attract talent, people can leave their jobs to start new companies, etc. Companies raise workers' salaries to encourage them to stay.