The Only Engineering Metric I Use

Committed to Completed Ratio

It encourages completing things and only committing to what you can complete.

It's legible, easy to understand by engineering, product, and management, pointless to game, and positively reinforces completion. It's quite difficult to accurately predict when a complete feature will ship, let alone a whole product. But, if one breaks down a feature into its legible constituent components and then commits to completing just what is within that (which also necessitates any required communication to arrive at understanding the requirements) then over time you can get quite good at predicting what you will be able to get done in a sprint and better at only committing to what you believe you can actually complete.

 

Sources of inspiration for this:

Though if you are interested in a good book on loosely related subject, highly recommend "Principals of Product Development Flow" https://amzn.to/3Ox4PgB