An extension of this your-child-is-not-an-adult observation is that it is probably not a good use of your time to think a lot about why your small child is having a tantrum. There is a strong temptation to try to figure out what exactly is the issue—to try to get them to articulate the precise problems they are having. Even if they can talk, this is likely to be fruitless, since they probably do not know. Tantrums happen for all kinds of reasons. Working on disciplining the tantrum behavior is the goal.