This is about misbehavior.
It's based on an answer to Merge tag "misbehavior" into existing tag "behavior" but I decided to turn it into its own question. I thought about it and believe that merging is not possible. But let's review the case first:
Tag wiki excerpts:
Why do children act the way they do? Use [discipline] for questions about enforcing your rules.
Questions regarding analyzing the reasoning behind a child's misbehavior. See the "discipline" tag for consequences of misbehavior.
Basically, misbehavior is behavior's evil twin.
There are currently 70 questions tagged misbehavior and when you have a look at them, you notice how often it was misused. The questions are not about "analyzing the reasoning" but about how to deal with misbehavior. However, the tag is not necessary for this purpose, since that's already covered by discipline.
Since there are so many questions tagged misbehavior and it was misused so often, I came to the conclusion that merging is the wrong approach (behavior makes no sense for most of these questions). There are too many nuances to consider. (For sure, it's possible that there weren't too many misbhevaior questions when the merging was suggested).
Here is a rare exception, tagged behavior misbehavior. And another one, with the same set of tags.
It seems that if misbehavior was removed where wrongly used, not much would be left - including a reason to keep misbehavior.
But I do not want to blame the OPs, since it's quite intuitive to (mis)use that tag - your child misbehaves, so you tag it like that. And most parents prefer making the misbehavior stop to analyzing it. On the other hand, behavior is so abstract, that the correct usage follows more intuitively.
Unless misbehavior gets a new meaning (and the tag wiki excerpt is changed), it seems to be pretty useless. But even then it may be too broad and more specific tags (like the already existing violence, tantrums etc.) may be useful or should be created.
How to handle misbehavior?
Keep it, and if we do, then what should misbehavior become? The way it is now, it doesn't seem to work.