Here's why:
* He was the first European to sail around the southern tip of Africa, a journey that was incredibly difficult and dangerous. He faced storms, mutiny, and the fear of the unknown.
* He never gave up on his mission, despite setbacks and challenges. He was committed to finding a sea route to the East, and his persistence led to a major geographical discovery.
While other character traits like courage and leadership are also associated with Dias, his unwavering determination is one of the most significant.