We all know that Code Reviews are a good thing, especially for a senior dev to review a junior dev's code. But it is also beneficial to have the junior developer code-review the senior dev's work:
- The junior dev see what good code looks like
- The junior dev may still catch something - even senior devs make mistakes.
- It sets a good role model - if even senior devs are having people review their code, then certainly junior devs should be too.
- It offers humility to the senior dev - If you only review other people's code, and no one ever reviews yours, it becomes one-sided, and is easy to get into an ivory-tower mentality of only criticizing other code without accepting criticism of your own.
- It prepares the junior dev to possible take over easier parts of the senior dev's code, freeing up the senior dev for other important tasks.