One stray male or a hermaphrodite in the tent will pollinate everything, and a seeded plant puts its energy into making seeds instead of resin. Tested THC on seeded flower routinely comes in several points lower, on top of the weight lost to the seeds themselves. Checking for early male flowers at the nodes, which the photo guide on https://potentthcseeds.com covers well, is a weekly habit worth building even with feminized THC seeds. Catching one plant early saves the whole room.