While a college education can help provide the tools to succeed, it is neither a guarantee of nor a prerequisite of success. Success depends on a lot of factors including motivation, desire, business savvy and luck. Many very successful business people, such as Bill Gates, do not have a college education.
Becoming successful without going to college is certainly possible, as many NBA, NFL and music stars will testify. It is definitely more difficult, though, because very few people actually have the large amount of raw talent that it takes to succeed without a college degree. Some people, though, like Bill Gates, just have that ability.