Retention is a terrible thing to goal on. It's almost impossible to drive in a meaningful way in a short term. Ultimately, you want to find a short-term metric you can measure that drives a long-term output.
Leading indicators beat lagging outcomes
Growth → Experimentation & Metrics
The metric that I think is slightly more actionable is a little harder to define, but so much more helpful in my opinion. It's what I call a market health metric, and this is basically think of your proxy that is the best predictor of your liquidity.
There is no such thing as a long feedback loop. And the way you choose to shorten the feedback loop is to say, what are the things that are correlated with the outcome that I eventually desire?
We identified these things on our flywheel. And this identification of these things was such a critical moment for the company because then it realized, 'Okay. Well, what we need to do is spend our time focusing on how do I measure each one of those things, and then how do I improve each one of those things?'