4 months into a new job, and I realized I had contributed about -4000 lines of code. I thought, how weird it would be to explain (especially to someone less technical), that I'd pretty much just been deleting code since I started. I'd also added a number of important features along the way.

Since then, I've taken some pride in trying to be a "net negative" (by line count), contributor to any code base I work on. Not always possible, but it's a good mindset to strive for leaner designs/implementations.