What makes a successful waterfall project?

I recently posted a question on linked in wanting to hear from people who have either led or been a part of a successful waterfall project.

Here's the link. There a some awesome answers. What's interesting is that what is required for a successful waterfall project is clearly defined scope, engaged sponsors, and a great, empowered team. Sadly, I rarely see all of these occur in the wild. And, these are the primary elements of what's necessary for an agile project, explaining why there is a higher success rate with agile projects.