Every KPI is a metric, but few metrics deserve to be KPIs. A lead generation campaign might track cost per lead and the share of leads that become clients, while a brand-building effort might track reach among non-followers, saves and branded searches. The right choice depends on the goal, so setting the goal comes first.
The common trap is choosing what is easy to measure instead of what matters, which is how vanity metrics end up in reports. Another is measuring too much: a dashboard with twenty KPIs has none. Reviewing the same few numbers at a fixed rhythm, monthly for most small businesses, makes trends visible and decisions easier.