I recently took a look at Factor, and the idea of having a language based around the concept of a stack is very interesting. (This was my first encounter with a stack-oriented language.) However, I don't see any practical advantages of such a paradigm. To me, it just seems like more trouble than it's worth. Why would I use a stack-oriented language such as Factor or Forth?
I'm ignoring factors (excuse the pun) such as the availability of tools and libraries. I'm asking only about the language paradigm itself.
Stack orientation is an implementation detail. For example, Joy can be implemented using rewriting - no stack. This is why some prefer to say "concatenative" or "compositional". With quotations and combinators you can code without thinking about the stack.
Expressing yourself with pure composition and without locals or named arguments is the key. It's extremely succinct with no syntactic overhead. Composition makes it very easy to factor out redundancy and to "algebraically" manipulate your code; boiling it down to its essence.
Once you've fallen in love with this point-free style you'll become annoyed by even the slightest composition syntax in other languages (even if just a dot). In concatenative languages, white space is the composition operator.