I've been working in a call center (tech support for a pay TV company) for two years - and it wasn't hell to work there. It became later, I heard, months and years after I had left (no causal connection). The reason is plain simple: The amount of money that customer relations should cost.

When I was working in said call center, it was policy that customers should have a fulfilling experience if at all possible. We were allowed to make and schedule call-backs and these were actually done. We were small case-managers, honest ones, as our possibilities were quite limited - as in most situations with first-level support. There was no "maximum time" rules. No high-score lists for the number of requests handled per hour.

Policy changed later. A "2 minute" rule was established. Feedback talks by team leaders were set up where it wasn't strictly followed. High-score like lists were put up. Tech support was encouraged to sell stuff, like bigger contracts - and the "top ten" scorers on the contract-offer list got rewarded.