TLDR: Yes, blockchains do get removed from Bittrex and we're always taking feedback from our users on how quickly we should remove them.

To properly answer your question, you should understand one of the core tenet of our business. Bittrex exists because we are passionate about digital currencies and we want to be a platform for innovative technology and blockchain businesses to thrive.

There's some valid criticism that when we first launched Bittrex, we added any coin under the sun. We felt that was fairer than the exchanges that extorted money from coin developers to get their tokens listed. As the market evolved, you will see that our standards have evolved as well. We have a published set of compliance rules and continue to raise the bar on coins being listed. You probably notice that our rate of additions is significantly lower than before. https://bittrex.zendesk.com/hc/en-us/articles/202583854

The real question is what to do with the coins that are already on the exchange today. We routinely weed out bad coins. If the blockchains are in a dangerous state, we attempt to work with the development team to fix it or we give notice to traders that it is going away. That's the easy case.

But there are a lot of smaller blockchains run by garage developers that are interesting and innovative but have a very small following. Maybe the coin launched before the big crowdfunds and have no marketing money? Maybe through events that occur in their life like a heart attack, a death in the family, or other debilitating event, the developer had to take a break for a month or two? Or low volume charity coins?

And of course, what happens to users who hold coins on a blockchain that is only traded on Bittrex? As time has gone on, our selections for blockchains have gotten better and this has been less of a risk but we do carry a legacy back log.

Anyway, there is a balance we're trying to strike and we're willing to carry some smaller blockchains and give them a shot.

I think my next post will be "which coins should Bittrex delist and why?" :)