Conspiracy theories usually come up after major events like a financial crisis, terrorist attacks, natural disasters, the death of high profile people, etc. People try to find out what actually happened, and so they some up with various perspectives. They try to make sense of the situation by connecting the dots. Many people believe in conspiracy theories for the following reasons.
Our brain patterns
Our brain tries to find patterns. It interprets various events and tries to connect them together in a meaningful way. Our brain prefers conspiracy theories rather than events or occurrences that are not connected. We try to conclude things from our social status, cultural orientation, past experiences, etc. Our desires and intentions also interrupt our beliefs and thus make us believe many conspiracy theories.
We try to find comfort and safety by believing in conspiracy theories. Our brain is receptive to an unknown threat. So, we accept things that we find comfortable believing in.
Sense of belonging
When you believe in a thing that a group of people believes in, it gives us a sense of belonging. We get drawn towards people having the same beliefs. So, no matter how bizarre the idea may be, if we see them believing it, we start believing it too.
Almost every major events lead to conspiracy theory. From the sinking of Titanic to the presidential election winning of Donald Trump, each of these events has given rise to conspiracy theories. People will keep on believing conspiracy theories in future as well.