I appreciated the role of a maintainer when I created a PR to add a new feature to a large, complex (and for some companies, critical) open source project 8 years ago.

As it turns out, the things I didn't understand about that project dwarfed -- by orders of magnitude -- what I thought I understood, but a maintainer worked with me with patience and a sharp eye, albeit in fits and starts over a period of 3 months. The implementation went through several revisions before the 700+ lines landed into the codebase (merged by that same maintainer).

Since then, I submitted only bug fixes to that project, because it seemed like less of a burden on maintainers and hopefully even lightened their load a tiny bit .