Yeah the formulation is quite biased, but to some extent there is some truth in the statements: > Your codebase is old, large and has been working fine without

Yeah the formulation is quite biased, but to some extent there is some truth in the statements: > Your codebase is old, large and has been working fine without static type checking for years. While Python’s type system is designed to allow gradual adoption of static type checking, the total cost of adding type annotations to a large extant codebase can be prohibitive. That's a convoluted and quite dishonest way of warning that you're trapped if you don't enforce types from the start; but it does have the merit of being on the list.