Factor ETF (Smart Beta)

Hey, this might be a noob question but could someone maybe help me out here 🙂

If I buy a factor ETF (for example Edge ETFs by iShares). In this case I buy a value etf.

What happens to companies, that get overvalued in the holding time? Do they just drop out of an index?

Or another example: small cap etfs.

If the companies get to be mid cap, do they just drop out of the etf or what happens?

Thank you and sry for the noob question