[user5994461]

I mean that good developers will migrate toward local companies that have good work conditions, good money, good projects, and good co workers.

The companies you quote are not better than a middle grade outsourcing company in these regards, so they're not stealing their talents. If they are the best companies you could think of, that explains why you can find decent developers in the local outsourcing firms.

[qaq]

Well the above to one extent or the other have all of the above but outsourcing companies are on par as far as perks. I am working for fairly large public US company and all of the above mentioned have nicer offices and more perks :). The reason I mentioned these is because they are to some extent well known.