I will attempt to explain what I think you should be researching before jumping into any DEFI project.

There are two sources of yield that I think are pretty important and should be discussed. Yield in the form of emissions and yield in the form of protocol revenue. Emissions can be anything that the team behind the protocol decided it to be (or the DAO). So that could be native token, grants, fundraisers, etc. Protocol revenue are collected from active users or other protocols that interact with the platform. Like how Uniswap and Sushiswap collects fees on trades.

Before jumping into it something, figure out how or where the yield comes from and is that source sustainable. Also, how does it benefit whales and the average user in the short term and are there mechanisms in place that improve the performance of the protocol over time? For example, one of the major issues facing degen protocols is that they are not sustainable. If you find one that is, focus your attention there. Of course, there's always the reputation of the team to take into account as hacks/exploits do happen even to best of the best.

At the end of the day, if you're not sure about whether or not a certain protocol is good or bad, just watch it for a week or two to see how it performs.