What exactly made Nero a bad example of a ruler?

Nero's rule actually started off reasonably well. His predecessor, Claudius, became increasingly paranoid as his rule wore on, and the on-and-off spates of treason trials and secret denunciations left upper-class Rome on edge. Nero came on the scene as a well educated golden boy, surrounded by high expectations. read more

Nero got a bad rep mostly because he was the last of the Julio-Claudian dynasty. The emperors that followed had an interest in making their predecessors look bad, thus making their own reign justified. Now for the details in your question: Nero didn't 'fidget' when Rome burnt, he fiddled (played the violin). read more

Nero (A.D. 37-68) became emperor of the Roman Empire after the death of his adopted father, the Emperor Claudius, in A.D. 54. The last ruler of what historians call the “Julio-Claudian” dynasty, he ruled until he committed suicide in June, A.D. 68. read more

Nero might have been a pretty unpleasant fellow in a thousand ways, but since he was out of town at the time, I doubt that he was the incindiary. So much has been written of how Christians suffered in the aftermath that I'll only say that there were some real refinements in cruelty practiced. read more