A number of viners have left over the years. There are certainly reasons for why people would be frustrated to the point of leaving the vine but on the other hand Newsvine strikes me as one of the very best forums available.
No doubt some people leave Newsvine and do not find a substitute; they just end online interactions. But those who want to continue interacting online go somewhere. What online forum is technically superior to Newsvine? Facebook? Twitter? NT? Why are these improvements?
Where do they go?