I’ve worked on big projects, small projects, in huge teams and by myself, in fossilized federal agencies and cool Silicon Valley companies. I have learned and used at least twenty programming languages. I’ve lived through waterfall/BDUF (big design up front), structured programming, top-down, bottom-up, modular design, components, agile, Scrum, extreme, TDD, OOP, rapid prototyping, RAD, and probably others I’ve forgotten about. I’m not convinced any of these things work.