Great question. There's an explanation here. It sounds like this only applies to dry brining, in other words, a wet brine or salty marinade would skip the first

Great question. There's an explanation here. It sounds like this only applies to dry brining, in other words, a wet brine or salty marinade would skip the first stage. Dry-brining cuts out the unnecessary added water by using the natural moisture content of the meat to create a concentrated brine that, when given enough time, is naturally absorbed back into the meat before cooking. Season a steak with kosher salt, and within a few minutes, you will witness osmosis at work: Liquid from the steak will bead up on the surface of the meat, drawn out by the salt. Wait another ten minutes, and that liquid from the beef will have started to dissolve the salt, forming a concentrated brine https://www.seriouseats.com/how-to-dry-brine https://www.seriouseats.com/how-to-dry-brine