One especially is in the case where it's boilerplate code that does not rely on any real deep thought but writes itself, and with the possibility of bugs in it, most of all. Anyone can make a simple typo or forget something in the endless boilerplate.
Maintainers are bottlenecked by the rate we can (re)read. Boilerplate is the problem that makes us want powerful languages; if it didn’t matter we could have stayed with assembly.
It also gets in the way of reading code.