An interview is about to show that you are experienced. What else then a commercial project shows that you have this experience?
You were motivated enough to do a commercial product. Hundreds of other candidates would be happy to have at least one small commercial product to show.
I would hesitate presenting a project which was a total commercial failure. For example, just looking at the summary, the person understands that you expected the product to be sold to thousands of people, and he sees that this is one of the worst selling projects on the marketplace.
On the other hand, there is nothing wrong about showing that you learn on your failures.
This project... em... I don't know what happened... well... I had an idea... you see... and finally I couldn't sell any copy... I don't know why, maybe those buyers are just stupid to see how great it is...
is not something you would like to say in an interview.
I know, it failed. In fact, when I started this project, I didn't expect to sell it at all. It was just a small project of mine, a simple app which was intended to help me in my daily work. Then I've shown it to a few friends, they found it great, and I decided to sell it.
But then... I learnt that you can't just sell something which works on your machine. There are chances that it will just crash on a machine with a different configuration. Then people started to bombard me with e-mails about the bugs they encounter.
I learnt that when you have a commercial-scale product, you also must have a bug tracking system, a version control is a must-have, you must have a relation between bugs and releases, then you must find how to update or, better, auto-update the software.
Moreover, the original architecture of the piece of software was not solid enough to accommodate all those changes, making it difficult to fix bugs and add features without rewriting everything from scratch; even constant refactoring wasn't enough.
And finally, I didn't have time to deal with commercial aspect of the app and the support, so I stopped selling it.
rather shows that you received a damn good experience making this product. Yes, commercially, it failed. But for you as a developer and for your career, it was a huge success.