Not really sure what your objection is; what exactly difference you see between "maintainable" and "easy to work on"?
Could it be that a good definition of maintainable is simply "easy to understand by others"? Then, of course, code earlier in the life cycle tends to be easier to understand.
Then there could be a difference between "easy to work with" (by the original author(s)) and "easy to understand by others". But assuming original authors were good programmers, I am not sure how they could cause this difference to occur.
Could it be that a good definition of maintainable is simply "easy to understand by others"? Then, of course, code earlier in the life cycle tends to be easier to understand.
Then there could be a difference between "easy to work with" (by the original author(s)) and "easy to understand by others". But assuming original authors were good programmers, I am not sure how they could cause this difference to occur.