Lines of code and readability are both surrogate measurements for codebase complexity. People focus on lines of code both because it's easy to measure and becau

Lines of code and readability are both surrogate measurements for codebase complexity. People focus on lines of code both because it's easy to measure and because readability doesn't go down linearly as codebases increases - there are discontinuity spikes. Once it grows past a certain size, you need the right kind of IDE, etc. to cope with the conceptual sprawl. People start duplicating functionality because they aren't aware things already exist, minor details that handle historically recurring bugs get overlooked in the noise, it takes much longer for new people to understand the codebase, etc. A 100k codebase is not just ten times harder to maintain than a 10k codebase.