I know that we should never share anything negative about a former employer, colleague or job experience, in an interview situation for example. I understand why and I don't disagree. However, sometimes those experiences provide valuable insight and context into who we are and why we want the job.
For example, I was inspired to pursue and career shift to employee engagement based on an uncharacteristic bad experience at a former employer. Is there any way to talk about this besides calling it "a bad fit," or dancing around what really happened? Is there any way to talk about the negative without it being, well, negative?