What’s the difference between infrastructure and brand-level reputation?

Infrastructure reputation attaches to the technical components sending your mail:

IP addresses, server configurations, and ESP relationships. This reputation can be changed by switching providers or IPs, though the underlying problems must still be fixed.

Brand reputation attaches to your domain identity:

The reputation follows your domain regardless of infrastructure changes. Switching ESPs or IPs does not escape domain reputation. This is permanent brand equity, positive or negative.

Modern providers emphasize brand reputation because infrastructure is easily changed. Domain identity is harder to abandon and better reflects true sender behavior over time.

Infrastructure reputation is like a ship's inspection record. Brand reputation is like the captain's license. You can charter different vessels, but your personal credentials follow you to every port.