Why? Because of lack of liquidity. I know it's very easy to create a token, but is not easy to get liquidity for the token, i think token should not be measured by marketcap, but by Liquidity. I ones saw a token with $10 billion marketcap but with only $5k liquidity, how can you explain that!!.

Only Coin should be measured by marketcap because it's independent, it does not have a trade competitors in his Blockchain, but it can only be trade outside an open market with other Blockchain.

My conclusion, before you buy any token make sure to run a background liquidity check.

My recommend, from $50k upwards is good for a Liquidity, for to  you to invest, and make sure to check that the Liquidity is locked, at least for some time.