How do you choose metrics, KPIs, and success criteria?

Question

Accepted Answer

**Metrics** quantify what's happening; **KPIs** (Key Performance Indicators) are the few metrics that best reflect success against a goal. Choosing them well means defining what success looks like *before* you build — so you can actually tell whether the work paid off.

## Start from the goal

```text
1. What outcome are we trying to achieve?
2. What metric would MOVE if we succeeded?
3. What's the current baseline and a realistic target?
4. How and when will we measure it?
```

If you can't name the metric that would change, you haven't defined success clearly enough.

## Good metrics vs. vanity metrics

```text
VANITY (looks good, means little):  total signups, page views, raw downloads
ACTIONABLE (drives decisions):       activation rate, retention, conversion
```

Favor metrics tied to real value and that you can act on. A number that only ever goes up and changes no decision is vanity.

## Balance your metrics

```text
✓ Pair a primary metric with a COUNTER-METRIC (guardrail)
  e.g. "increase signups" guarded by "keep activation stable"
→ prevents gaming one number at the expense of overall health
```

## A concrete example

Goal: improve onboarding. A vanity metric is "users who clicked start." A real KPI is "% who complete onboarding and return within 7 days," guarded by support-ticket volume so you don't "improve" the funnel by hiding a confusing step.

## A common pitfall

Goodhart's Law: "when a measure becomes a target, it ceases to be a good measure." Optimizing a single number invites gaming — counter-metrics and judgment keep you honest.

## Why it matters

Without success criteria defined up front, every launch becomes a debate about whether it "worked," decided by opinion instead of evidence.

Clear, balanced metrics turn product work into a feedback loop: you set a target, ship, measure, and learn — the foundation of improving rather than just guessing.