Defi is a scam! Having invested in defi I lost a lot of money, because a lot of coins are stamped every day, be careful with defi! 
My Friend DeFi first of all is not an investment . It is a blockchain application that leverages the power of consensus, speed and authenticity of a transaction. It's the strategy of which how would someone use DeFi as their investments that makes it complicated. Be educate as what everybody says and if it is too good to be true then think it over 100x before making actions.
I agree that it is necessary to check everything before investing. All DeFi projects needs more liquidity. There are services like https://www.koinal.io that allow to buy and sell cryptocurrency directly from bank card, it will increase the liquidity of the coins.