The zodiac sign with the most ambition is Capricorn!

Capricorns Have Determination: Capricorn individuals may not flaunt their ambitions as openly as signs like Sagittarius or Aries, but their ambitions run deeper, larger, and are more long-term. They possess the ability to plan and execute with precision, along with self-discipline and patience.
Capricorns Exhibit Great Endurance: In addition to their strong ambition, Capricorns are known for their stability, resilience, attention to detail, patience, and high competence. They are diligent, serious, and reliable, willing to put in the hard work to achieve their goals. Don’t be fooled by their outward appearance; behind their shrewd and cautious demeanor lies an exceptionally strong ambition.
Capricorns Are Highly Rational: Capricorns often have a sense of solitude, as they tend to be quite independent and rational due to their frequent self-reliance. They are typically workaholics and find solace in their jobs. They don’t feel lonely when they have work to do. They engage in tasks they enjoy, and while they may be troubled when things go wrong, they experience a strong sense of accomplishment when they succeed. Their naturally introverted nature means they rarely seek help from others, even when faced with challenges.