True; but you can recognize maintainable code when working in a larger team and ownership of modules changes a lot, which it should for any healthy project.
There are several universal things you can do to ensure maintainability, which are a no-brainer, but don't happen because of various compromises that have to do with time and money - like code-reviews, having no module with a single owner, automatic tests, up to date documents / stories, etc...
If you don't do any of that, it's a no-brainer again that the project will not be maintainable; but it can still be beaten into shape later if the original devs weren't totally insane :)
There are several universal things you can do to ensure maintainability, which are a no-brainer, but don't happen because of various compromises that have to do with time and money - like code-reviews, having no module with a single owner, automatic tests, up to date documents / stories, etc...
If you don't do any of that, it's a no-brainer again that the project will not be maintainable; but it can still be beaten into shape later if the original devs weren't totally insane :)