This is what Andre brought up on Twitter and something I thought about as well.
Currently, for a particular vault (yUSDC for example), Andre displays the APY once a day on Twitter. While the liquidation risk is super low, some people might feel that it is TOO safe and some money is left on the table.
By introducing various risk levels (the risky one might have a lower health factor or mine a riskier pool), users can choose a vault suitable to their risk appetite.
This is akin to traditional finance where people choose a suitable mutual fund based on their personal condition. If they are risk averse, they pick a safer fund (bonds/large cap stocks); if they desire a higher return, they would go for a more aggressive fund.
A side benefit from this is that we can see what people prefer, so that we can create products with better product/market fit in the future.