Custom Metric

A custom metric is one a user defines themselves by combining or filtering existing data, rather than being limited to the tool's default metric list.

A custom metric answers the reality that no tool can know in advance every business's important metric; 'the mobile organic-channel sign-up completion rate' is a metric only you need. Its power is flexibility, but that same flexibility brings two dangers. First, definition sprawl: if everyone builds their own, you soon have three 'conversion rates' with three different definitions and meetings wasted on which is right; so a custom metric needs governance and documentation. Second, a meaningless metric: the ease of building means you can make one that is mathematically correct but decision-worthless. A good custom metric starts from a decision question, not from 'what things can be placed together'.