One number.
Not fifteen.
Teams tracking thirty metrics track none of them well. Pick the one that tells you the truth at your stage, plus the two things that move it.
Stop looking at these
How to choose a north star metric
A north star metric is the single number that best represents whether people are getting the value you promised. Not revenue - revenue is the consequence. Not signups - signups are the hope.
The test a good one passes
If this number goes up and nothing else changes, is the business genuinely healthier? Signups fail that test instantly: a thousand signups who never return leave you worse off than before, having burned attention you can't buy back. "Weekly active teams with three or more members" passes it, because it's very hard to fake and very hard to misread.
It changes with stage, and that's correct
Pre-product-market-fit, the honest north star is usually retention or activation - evidence that anyone wants this at all. After that it shifts toward growth of the value-delivered number, and later toward revenue efficiency. Picking a late-stage metric early is how teams end up optimising a funnel that has nothing to funnel.
The two inputs matter as much as the star
A north star you can't move is a wall poster. Each one needs two input metrics that you can actually act on this week - that's the difference between a metric that guides work and a metric that just judges it.