Why not just say "Agile Works Sometimes"? Or "Agile Can Work"? Because when "Agile Works" is touted, and then things go wrong, people get blamed, vs the actual processes and concepts. If "Agile Works", but we're not getting the results, then someone must be doing something wrong - can't be "Agile" that's wrong (for this scenario).
"Agile" software development doesn't work when there's 5 non-technical stakeholders and 1 software developer.
And if you are doing "Agile" but it's not working... then you're Doing It Wrong(tm). Right?