What metrics do technical product teams look at to define success? Which do you find to be the most important?

This depends on the goals of your product. In general, you want your key metrics to be aligned with what you and the organization considers the top goals of the product. 

For example, this might be revenue from your product, or number of other products customers use alongside your product. There would also be secondary goals like your adoption, retention and growth.

I'm excited to see a question about metrics – being data-driven is super important!

First, keep in mind that there are various types of product metrics. I think of them as Usage, Business, and Performance.

• Usage metrics might include daily active users, feature usage frequency, and time spent on the product.
• Business metrics can cover churn rate, revenue per customer, cost per customer, and monthly recurring revenue.
• Performance metrics focus on availability, response time, and defect rate.

Of course, these are just a few examples – you could track many more metrics. The key to deciding which ones to measure is to focus on the outcomes you want to achieve. For instance, if your CSAT score is low and you think it's due to performance, define performance metrics that will impact CSAT, like UX latency or uptime. Measure your baseline, design experiments to improve performance, run those experiments, evaluate the changes in your metrics, and then see if that boosts your CSAT.