How bad was Caligula?

[Nathan Ross]

Surely Caligula would have learnt how hard a job governing Rome and the Empire was as well as what power the Emperor had?

Oh sure - we can assume that there was more going on at Capri than kinky sex and random executions. But, as Jass mentioned above, previous imperial heirs-designate were often given an active and responsible role to acquaint them with the exercise of power and its limitations: leading armies, governing provinces and giving speeches to the senate. Other than his funeral oration for Livia, Caligula seems to have had no public role at all before his accession, no responsibility for anything.

This is what I meant by the effects of power - he would have seen various family members die in suspect circumstances, he would have seen the senate cowed by the Praetorians, and he would have experienced and learned about Tiberius's methods for clinging onto power. But he would had no practical experience of what holding that power actually feels like, and what it entails. Not surprising if he found it dangerously intoxicating...