Issues resolved is definitely the most gamed metric I’ve seen of late. I left an organization that shipped most of it’s work to another vendor as “application maintenance.” Over the years those teams kept growing and so did the issues. We pointed out their same size ticket completion metrics were lower than acceptable compared to other teams, they responded by closing tickets prematurely or just not working them at all and submitting then with entropic 0 change commits. We pointed out their accuracy rate was abysmal, they responded by filing bugs as user stories, and sent out the most maddening email to @all come perf review time celebrating 0 defects, 1200% productivity increase YOY.
Definitely the most singularly useless, gameable metric in modern development.