There were some enjoyable parts, but I personally thought the job was quite stressful because of the high quota. Psychologically, I found it difficult to reduce my quality of work enough to meet the quota. Many examiners at the USPTO can knowingly reduce their quality to an appropriate level, but I wasn't one of them. (Others don't care about quality or aren't able to discern good quality from bad.)
I stopped for the simple reason that the job was far too difficult, and poorly paid on top of that.
Interesting. Did you enjoy it? Why did you stop?