The concept of heaven and hell is explained clearly in Bart Erhmans "Triump of Christianity"

Heaven for the weather, hell for the company.

When I was a child we moved every few years and usually went to the nearest Protestant church. So I was exposed to churches of various flavors: Presbyterian, Methodist, and Congregationalist. The first two talked about hell -- the third didn't. By the age of about ten I had already decided that there couldn't be a god because of the concept of hell -- I have never thought of myself as capable of sentencing anyone to the kinds of horrors that were described as existing in hell. And, I figured that if I, a definitely flawed human being couldn't there was only one explanation: god must not be the 'all loving' figure he'd been described as being. Because I believed that any being that could send people to eternal damnation must be deeply flawed -- even more flawed than me. So logically, in my mind neither hell nor god could exist.