Whether an event is traumatizing to a person depends not just on the event but on the person. There's an interaction somehow. And some people are more prone to being traumatized than others. For example, some people survive a tsunami and are not traumatized. Others are. It could be genetics that helps make a person more easily traumatized and environmental factors too. They have done studies on factors in a person that predispose to or protect them from being traumatized. For example, for men, those who are married are less apt to be traumatized if exposed to an event that could be traumatizing (like a tsunami). (As I recall, this protective effect of marriage does not hold true for women.) So there are these protective factors such as marriage for men but also predisposing factors too. And genetics. It all adds up to some people being more easily traumatized than others. I don't think people are deliberately creating their trauma but just very sensitive to trauma. Hopefully, they can make changes to become more resilient--a good goal for therapy, I think.