Hey, it's…that person! If only you could remember their name, backstory, abilities, or motivations, maybe you'd actually like The Boring One. But as it stands, nothing about them seems all that memorable, and your other party members are so much more interesting by comparison. It's not that they're downright awful--they're just so "meh." If you're going to be spending 80 hours with a virtual ally, it sure as hell isn't going to be The Boring One. Yeah, you'll talk to them between quests, but only to see if they've somehow developed any kind of distinctive personality yet. Spoilers: They haven't, and likely never will.
Notable examples: Kaidan (Mass Effect series), Carth (Knights of the Old Republic), Kellam (Fire Emblem: Awakening)