Something that I've found helpful is taking the words "behave" and "misbehave" out of my vocabulary. Kids, like adults, get frustrated, misunderstand, miscommunicate, make assumptions that aren't true or don't pan out, get facts wrong, get tired, hungry, bored, lonely, aggravated, and sometimes find themselves in over their heads. And their behavior reflects that. But unlike adults, kids don't have very much experience in the world, so they're not very well equipped when things go wrong. Their behavior tends to telegraph a lot of what's going on with them as a result.
Especially with my first kid, who got to experience the steep part of my learning curve as a parent, when I thought about his behavior in terms of whether or not he was "behaving" I missed seeing the reasons behind his behavior - I wasn't looking for reasons, I was looking for performance. The more I looked for reasons, for what his behavior was communicating, the more I knew about him as a person, and the better I was at being his partner.