North Star metric
B1CEFR level
55/100Rarity: uncommon
TechnicalRegister
The single measure that best captures the core value a product delivers to customers and that a whole team aligns its work around.
We settled on weekly active teams as our North Star metric because it tracks retained value better than sign-ups.
Rarity runs from 0 (a word everyone knows) to 100 (almost never seen outside specialist or literary writing). Level is the word's real difficulty on the CEFR scale, from A1 to C2.
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