North Star metric
The single number a whole team steers by, chosen because it goes up only when customers actually get value.
See it
What it is
A North Star metric is the one number you'd keep if you had to delete every other chart. It should track the value customers actually get, not the value you extract from them. Airbnb's classic pick was nights booked, Spotify's was time spent listening, Slack's was messages sent within a team. Notice the shape: each one goes up only when someone genuinely used the product.
Reach for it when a team keeps arguing about priorities with different scoreboards in hand. A good North Star has inputs you can name (a handful of levers that move it) and a cadence fast enough to react to, which usually rules out revenue and definitely rules out anything reported quarterly.
Gotcha: pick a number that can be gamed and it will be gamed. Optimize 'pageviews' and someone splits an article into twelve pages. That's why a North Star is paired with guardrail metrics (churn, refund rate, load time) that must not degrade while the main number climbs. Also: one product or business model gets one North Star, because the alignment is the whole point. Teams do not each get their own; they own different input metrics that feed the same number. A company running genuinely separate products is the exception, and each product can carry its own.
Ask AI for it
Pick a North Star metric for my product. Read the product description below plus any context already in this project, state the assumptions you are making, and name the core value exchange yourself rather than asking me. Then propose 3 candidate metrics stated as a countable event over a time window (like 'weekly projects shared per active team'). For each candidate, list the 3 to 4 input levers that move it, which team owns each lever, the way it could be gamed, and 2 guardrail metrics to watch alongside it. Reject any candidate that is pure revenue, pure signups, or reportable only monthly. Finish by recommending one, with the reason, in the same response. Do not ask me follow-up questions.