Usually when people ask this question they are looking for a sign that a psychological or traumatic event that I associate with the church, god, or religion somehow drove me away from religion. It’s not that complicated, though. I do not hate god because someone close to me died or anything else like that. I would have to believe in a god in order to hate that god.
There are some individuals that others may call atheists because of emotional or psychological reasons (associated with a traumatic event). However, they tend to still be believers, but simply mad at god and are disassociated from their respective church. If you hate a god then you at least have some belief (however miniscule) that the god exists in the first place. It seems somewhat futile to hate something that you supposedly do not believe in. Some of these individuals finally lose their belief and become atheists, others find another religious path, and some return to their original religion or church. Unfortunately, there are no statistics that track these individuals so we may never know how many people who go through a “crisis of faith” become atheists, find another religion, or return to their original one.
I am an atheist because theism cannot and does not provide the answers that I seek. When I ask the questions that religion often use as their “trump card,” I am not satisfied with their answers. These include questions like, “Why Am I here?” “Where did I come from?” “What is the purpose and meaning of life?”
Theism, in my view, is superfluous in this modern scientific age of knowledge and the expansion of that knowledge. It is too abracadabra, hocus pocus, and illogical! Instead of intelligently looking for the answers to those psychological needs, people grab onto the easy answer from the religious “silver platter.”
I am an atheist because I refuse to take the silver platter answers that the religions of the world dish out. I will travel the road less traveled and find the answers on my own. I will investigate all possibilities and intelligently eliminate those that are irrational.
I could write an entire book to answer this single question. I hope that as people ask questions the answers will help them understand why I am an atheist.