Definition
Keeping existing customers active and paying over time. Retention is typically more cost-effective than acquiring new customers — a small retention lift compounds significantly over years.
Why it matters
Retention is where the economics of a small business quietly get decided: keeping an existing customer generally costs far less than chasing a new one, and repeat buyers tend to spend more and refer others. For an owner, it's the difference between filling a leaky bucket and building a stable base of predictable revenue. The failure mode is that churn is easy to ignore because it's invisible day to day — no one sends a cancellation notice, they simply stop coming back — so without watching for it, a business can grow on paper while steadily losing the customers it already earned.