It is difficult to explain in one sentence the specific reasons for having psoriasis. 1. There is a relationship between psoriasis and heredity. The actual fact is that there is a tendency for psoriasis to gather in families, and if a parent or family member has psoriasis, the likelihood of the offspring getting psoriasis is relatively high. The actual fact is that you can find a lot of people who have been in the business for a long time. This is a good way to get the most out of your life.