Oddly enough, projects can fail for bad and good reasons. A bad reason is when the project lacks one of the essentials I listed on the previous page. It means the project could have succeeded, or could have been rescued as it was going off the rails, but someone wasn't doing their job, or management didn't care, or the team lacked focus or team-work.
But sometimes projects can fail (and by that I mean not reach their goals or deliverables) because of changes beyond the control of the project team. You'll see this in R&D and product development all the time - in well-managed companies. Especially in R&D where there is a lot of risk that a technology has to be developed or utilized. Let's use as an example drug development. Consider trying to develop a drug to cure lung cancer. First there is a big risk that no drug can cure the disease. You may pursue a promising line of research just to find out it doesn't work. Canceling that project makes sense. Or maybe the drug works in rats but not people. Or the drug is no more effective than an existing drug on the market, or is more expensive to produce than an existing treatment. Maybe it doesn't cure lung cancer but it does cure diabetes, but your company doesn't have any marketing expertise or sales force to address that market. In any of these cases, the best management decision might be to cancel the project and have the team focus on more promising research. That's a good project failure - because it saves time and effort in the long run.
If you're on a failed or canceled project make sure you understand whether it is a good or bad failure. On either, it is important to do a project post-mortem so you don't repeat the mistakes of the past.
