With 65 percent of projects adopting Agile practices failing to be delivered on time

They're not "failing to deliver", they're being Agile in disappointing everyone involved!

Projects where engineers felt they had the freedom to discuss and address problems were 87 percent more likely to succeed.

Which shouldn't surprise anyone, but I know some managers, directors and users loathe the idea of the people who'll do the actual job having any say other than "yes, sir".

In highlighting the need to understand the requirements before development begins, the research charts a path between Agile purists and Waterfall advocates.

Good documentation is critical and process-agnostic. If people can read and understand it, it's good. It's something that can be used as a shield and weapon against users/higher ups who want too much, it can create a trail of responsibility.