The paradox is that people don’t actually implement agile methodologies but rather try to shoehorn them into their waterfall mindset.
After several decades and several methodologies in a number of fields, I’ve concluded that very few actually think methodologies are useful. It’s always pick and choose or mix and match the various elements. This is all driven by the belief that my business is a special little flower and needs it’s own custom little process that only I can invent.