brick · v1 · 2026-08-03
The metric proxy
When a bond acquires a number, the number starts replacing the bond
How streaks, counts, and scores hollow relationships without taking any of your time, and the design test that separates a metric proxy from an aligned one. The canonical treatment of the metric proxy.
Around 2017, Snapchat’s streak counter ran an accidental experiment on a generation. A streak is a number attached to a friendship, the count of consecutive days two people have exchanged snaps, and nothing about it measures what any exchange contained; a blurry ceiling keeps the count alive as well as a confidence does. Within two years, it was widely reported that teenagers were handing over their passwords before vacations so a friend could keep their streaks from dying. Hold the arrangement still for a moment. The contact was daily and perfectly mutual, human on both ends, and the friendship had been hollowed into bookkeeping anyway.
That is the metric proxy, and the experiment’s value is what it rules out. Nobody was captured; a streak costs seconds a day. So the damage cannot be a function of time spent, and “screen time” is the wrong diagnostic axis entirely. The corrosion is structural. A countable stand-in replaces the quality of a bond with a quantity of it, and once the number exists, it does what numbers in incentive systems always do. It becomes the target. Maintaining the number substitutes for relating, loyalty converts into obligation, and the people become, to each other, the dispensers of the tokens the counter needs. Goodhart’s law, arrived in the one domain where the gap between measure and target is a friendship.
The test for designers is directional. Does the mechanic give the bond something to be about while staying out of its middle, or does it insert a number between the people? Like buttons and follower counts fail the test the same way streaks do, converting regard into tokens. And where a metric must exist, it can at least point at the outcome the people themselves want. Hinge’s We Met survey feeds post-date outcomes back into matching, which aligns the product’s number with the users’ actual goal rather than with the habit of checking. Alignment does not make a metric safe, but it decides which way the pressure leans.
The proxy also explains why so much relationship technology feels busy and empty at once. The numbers are all healthy. They are just numbers about themselves.