I was thinking about Sheila last night. She's the character that has lasted the longest. WJB antagonists always had a beginning, middle and end. The end was usually they were killed off for good. But Sheila was brought back from the dead and moved to BB to goose up their horrible ratings. WJB should never have brought her back. She should've died in the fire on YR. She's been overkill ever since. Her welcome ended decades ago.
Both are stale if we're being honest. Bradley ran out of ideas decades ago.
I would also add Ridge and Brooke redux as stale as hell.