The notion of meritocracy is this: through your personal strength and industry, you increase your ranking in society.
This is what I believe drives capitalism, and notions of productivity. Also, this is the ethos of America.
However, the downside of meritocracy is that its standardizes people and human beings, and gets rid of this notion of ranking.

For example, even Korea used to be a caste system; with the aristocratic Yangban on top, and the slave class (Nobi) on bottom. However, after American intervention in South Korea, Korean society is actually very very similar to American society: the harder you study, the harder you work, the higher you will test, and the higher university you’ll attend, which will end up giving you a higher paying job at a higher ranked company.