WTF “Building the right product”?

The main goal of PM is to build the right product. But If to be more rational and avoid philosophical things I tried to understand what does it means — “Build the right product” I assume that the best sign of “Right product” is viral growth.

Is if we need to make viral growth we need to work with AARRR metrics.

So depending what metrics we want to change (now is X -> we want Y) we need to think what feature we are need to build. So we have hypothesis: If we will build this feature this will change metrics to Y. Metrics.

And especially Product Management is using in following metrics:

• Activation (partially) — Make announcement about new feature to attract new users.
• Retention — What features build to make users use it continuously.
• Revenue — What paid features build to make users paid for it.
• Referral — What feature build inside the product to make it so cool to make users recommend it to their friends.

I understand than product is more than just features but I think this is the main.

And growth hacking is about how to make growth in Acquisition and Activation

So the biggest question: How to understand what feature we should build to change X metrics?

What do you think about it?