Could it be that agile projects fail more often (or take longer to complete) because people with a different "mindset" are able to work on projects like these because they are being enabled to do so due to a different "way of working"?
Example: We have a shop relaunch going on and marketing is in the lead. Project is almost double over budget and at least two months over time, they fail so set clear expectations and requirements and there's sprint after sprint after sprint to get things to a release-ready state.
Without agile project management this relaunch would have long been counted as a fail and consequences would have followed OR marketing wouldn't have been in the lead because they would not have been able to set expecatations and a clear goal from the start on.
Any ideas on that?