If you tell me your date of birth, where you were born, what your parents thought about politics and religion, and whether your relationship with them is sweet or bitter, I can predict a great deal about your values and beliefs. This is because we humans are tribal creatures. Our foundational knowledge is transmitted from the tribal members who nurture and educate us. If we are happy and secure within our group, we share their worldview, reasoning, logically, that many generations of ancestors have considered the evidence to arrive at an optimal interpretation. It can be tweaked, but few individuals are motivated to contest the entire worldview they have inherited.
Some people switch social class, political allegiance, religious affiliation or national identity. A few are trailblazing free-thinkers. Most switchers are simply unhappy with the tribe they were born into and willing to embrace the worldview of a new tribe.
Switchers are often attracted by a charismatic leader and then encounter a group of like-minded friends. Once the new tribe has formed, intellectual justification for the new worldview follows.