With these metrics, you discourage the sort of user who spends 3 weeks fixing a bug that's been in the code base for 3 years. In the end they removed one line, to fix the bug. By the metrics: -1 line. 1 Commit. Clearly they aren't doing as well as the person who added 1000 new lines of code... across 15 commits.
I have genuinely spent 3 days on one bug, and fixed it by removing one character.
Deleting code is often one of the best things a programmer can do.
But it's disincentivised.
5/n