The application outside of software is going to be subjective. One example in a PM class I took was building things, specifically things with very high risks in

The application outside of software is going to be subjective. One example in a PM class I took was building things, specifically things with very high risks involved like building a nuclear power plant. You want that to be done with waterfall and serious risk management strategies applied to everything. I think of agile as the concepts in the agile manifesto and lean techniques, not a specific framework, etc. I would generalize that agile works well when the output is digital. That isn't universal either, some digital outputs, movie post-production I imagine, require a waterfall of inputs to happen first. Solving world problems deals with governments and legal systems which are heavily based in documents, contracts and lengthy change processes. I can't see agile working for anything that is a "world" problem because of that.