The Crusade was a success in the short term. The Crusaders captured Jerusalem in 1099, and they established four Latin states in the Holy Land. However, the Crusades ultimately failed to achieve their goals. The Muslims eventually retook the Holy Land, and the Crusades left a legacy of violence and hatred.
Ultimately, whether Pope Urban II was correct in calling a crusade is a matter of opinion. There are strong arguments to be made on both sides. However, it is clear that the Crusades had a profound impact on the history of Europe and the Middle East.