[solve]

Retention and NPS seem orthogonal.

[ivankirigin]

Nope. NPS is a measure of satisfaction. You care about the word of mouth component, but it isn't measuring something different than retention.

[solve]

Nope. They're literally measuring two different things, return rates vs "would tell a friend" rates.

Whether those two happen to coincide is quite product-dependent. Finding examples where they significantly diverge is trivial.

[rgbrgb]

I'd say they're different, but definitely not orthogonal. NPS asks if you'd recommend the product, retention is how long you stick around after first use. Both metrics embed the user's affinity for the product (which is the underlying thing sama's saying to measure and improve).