There are some DeFi projects with impossible yield farming and earnings, this percentage are too high to be true, you can never see such on proof of stake coins yet there are many people investing in such DeFi projects, they won't last long and they will surely exit scam
yes, some give as high as 300% of above, it doesn't make sense for a true business that has a long term vision except they are only created for short term purpose, a look at such offer will tell you it is too good to be true, better to join for short term, make profit and get out as soon as possible.