There is a natural competition to become an "idea person" in an organization. If the project goes well, the idea person gets the credit. If the project goes poorly, the people who actually built it get the blame. And it takes far less work to produce promising ideas, than to actually build stuff. The result is that succeeding in getting other people to implement your ideas becomes a fast track to promotion. Unfortunately, the farther that you get from the actual implementation, the worse your ideas get. Compounding that is the fact that the ideas that convince executives far too often are the ones that play buzzword bingo in the right way, rather than the ones which are grounded in pragmatism.
This is why I've learned to be suspicious of anyone with a job title of "architect". Some are amazingly good. But most that I've dealt with, are decidedly not. But when you hear them talk about it, they always sound like they are amazing.