What were the technical buzzwords that companies used to signal hotness in the industry before the ML hype train (startup or not)?

I know on the process & management side for large organizations, there's been a revolving door of Lean/Agile/6 Sigma/ISO 9000, each with their own set of certifications, colored belts, and army of advisors/consultants.

I like the idea of always being retrospective and asking what can be improved, but it's made me a bit cynical seeing management chase fads based on whatever a vendor tells them.