It seems like a no-brainer to me, but I will say it anyway. Code reviews are a good thing. Some people may shy away from them because it may make them feel inadequate or like they are being judged. But the idea behind a code review is to learn.
Code reviewing is a great way for a developer (novice or otherwise) to track down inefficiencies or architectural problems with their code by using the experience of other developers as a tool. We all know that two heads are better than one, right?
Code reviews can also be a great way to track down vulnerabilities in your applications. This is especially true for novice developers or for developers who have not had any formal security training (most of us?).
I was recently at a presentation where code similar to this was displayed:
<cfif IsDefined("url.name") and Len(url.name)>
Many of the developers in the room had a hard time identifying the vulnerability. This is because we are not trained to look for them. We think so much about how our applications should be used, we sometimes don't think about how they might be misused.
By having other developers look at your code, you can discuss inefficiencies and vulnerabilities and learn how to look for these things so that you can recognize them in the future.
I'll be the first to admit that I do not write the best code. I definitely have a lot to learn. But at the same time, I also have a lot to offer. Perhaps, during my code review, I can teach something to those reviewing my code. Either way, the worst thing that will come out of it is that I will learn something.