Can working with Legacy Code be beneficial?

​Pretty much every developer has experience of working with a legacy codebase, yet for many, the idea of Greenfield work is the Holy Grail of software development.

But are we forgetting some of the benefits that come with this type of work and the boost it can have on your own development?

Here are a few reasons that stand out to me:

- Legacy code often means a clearer direction
- Your debugging skills increase quicker
- You can add improvements/refactor and see instant results
- Migration helps build your knowledge of new features

That's not to say that there aren't downsides to working with legacy code, and I appreciate often it's the sheer quantity of work with legacy that developers can be frustrated with.

Having said that, I'm curious as to how many of you would be the developers you are today without the long hours spent honing your skills with this sort of work?