"most of these people are better than the ones in Silicon Valley since they are working in their own country which the jobs are not much instead of migrating to a different place to find a job"
These people are better than the ones in Silicon Valley because they refuse to emigrate? I don't follow your logic.
Sorry, I probably didn't make myself clear (english is not my main language):
Here in Greece there are not too many jobs on local (Greek) companies because of the economical crisis and repression. Definitely there are more candidates than jobs. So most of these jobs would probably be given to the better / more experienced developers while, other, not so good developers will try to emigrate to other countries to find jobs.
Notice that there was no culture of emigrating here in Greece before the crisis, people seldom emigrated because the family ties are strong here and people are raised with a culture of loving their country and not wanting to leave it (and as I said in a previous comment Greece is beautiful - you only want to leave it if you actually starve). This has changed due to crisis of course but I think that a good developer will definitely be able to find a job here in a local company and not need to emigrate.
I see. What you mean is that the average employed developer in Greece is better than the average Greek developer due to competition for jobs and culture of attachment to the homeland.
This may be true, but it has little relation to quality of the average developer in Silicon Valley.
These people are better than the ones in Silicon Valley because they refuse to emigrate? I don't follow your logic.