You know.. it was probably a weird occurrence with me but I shall try:
I was born. I lacked a belief in everything and anything, from gods to hamburgers, cars to nice bottles of red. I didn't believe either way, I just simply lacked a belief. In time I learnt that bottles of red were real - (I gained an almost compulsive belief in them). My lack of belief in gods just never developed. It was like the goose egg that never hatched. It wasn't a choice, it was just the way the cookie crumbled.
Looking back I completely blame my parents. If they had have espoused a belief in some god then I most likely would have too. They didn't, my lack of belief never changed.
I have since heard hundreds if not thousands of claims that people label "god". I remember one of my teachers talking about Apollo and I'm like.. "pfft". I remember one of my teachers talking about yhwh and I'm like.. "pfft". It's a long list, trust me. I noticed that I relied on some human definition - and that is where the problem lied. So many billions of humans, so many definitions to laugh at. I suppose in hindsight at least these people had the courage to supply a definition. I realised that if, according to some, 'god' could not be defined then it was no wonder I lacked a belief and continue to do so. Define me a god and you'll get an answer, refuse to do so.. and what answer would you honestly expect?