What RUINED Hanna-Barbera?

Hanna-Barbera is a company that ruled televised animation for decades. There was a time when they controlled over 80% of the market but then it came crashing down. How did this happen? How did this studio fall so far from grace? "What RUINED/What's RUINING..." is a video series where Saber researches a topic, presents its history, and how it is or was presumably ruined: Saberspark is a YouTube channel who researches, reviews, and analyzes various movies and cartoon shows from the world of...