Execution Variables at Test Case Artifact.

I noticed on the Test Case Artifact there is a section that can be added for "Execution Variables", however I am not understanding what the use case for the "Execution Variables" at the Test Case Artifact.

It appears as though: 

·         you can add Project Variables to Test Case via the Test Case>Execution Variables selection

·         you can create Artifact Variables for Test Case via the Test Case>Execution Variables selection

However, in either case I see nowhere on the Test Case Artifact to Insert either Variable nor do these Variable push down to the Test Cases, Test Scrip….You can Add/Create these at the Test Script Artifact without them being on the Test Case Artifact Execution Variable selection. <o:p> </o:p>

Therefore, I am curious if there is some functionality I'm missing in regards to "Execution Variables" use at the Test Case Artifact.