The recent appearance of Defi project massively on services sections, Have kept me off balance. But I need to understand the future of Defi projects, and why stablecoin "Dai" is doing better than bitcoin and Ethereum on the long run? The disadvantages of DEFI project is an added thank you. 
It seems that what you are saying is a little confusing because what I have seen from a few years ago Bitcoin and Ethereum have always worked better than DAI tokens, and DAI tokens are also not included as stable tokens even though in terms of price they have not changed much.