The Free Ride

A remora rides a shark and eats what falls from its meals.

A remora's dorsal fin has evolved into a suction disc. It attaches to a shark, a ray, or a whale, feeds on scraps and parasites, and travels for free across distances it could never cover alone. The host is neither harmed nor helped in any measurable way. It does not feed the remora deliberately, does not benefit from carrying it, and mostly does not act as though it is there at all.

The vendor that scales exactly as fast as its client, and changes nothing about how either one operates.

A perfectly serviceable business can be built entirely on commensalism. Revenue rises when the client's usage rises. No integration deepens, no capability compounds, and nothing durable is created on either side. It is a fine position to hold. It is not a defensible one, because nothing was ever built that the client would miss.

The distinction from mutualism is not size. It is whether the relationship is chosen for a reason that could survive scrutiny, or simply persists because removing it has never seemed worth the trouble.