Sebastian Vettel Explains BMW's Decision Over His F1 Career

• Sebastian Vettel discusses his early Formula 1 career in a new ARD documentary.
• BMW initially supported Vettel but ultimately decided not to retain him.
• Vettel reveals his reasons for BMW's decision in the documentary Being Sebastian Vettel.
• Red Bull later signed Vettel, contrasting with BMW's choice.
• Vettel is a four-time F1 world champion.