I think there's even a warning for it.
There isn't; that is the entire point of this discussion. If a trade is initiated, there should be a warning tag and/or warnings for empty reserves. This is similar to a casino taking deposits while the hot wallet is empty for withdrawals, and clients are unable to withdraw. A simple warning tag for empty reserves should be implemented.
No there is a warning:
1. On the homepage, anyone can see the actual reserves before starting a new order:
2. Once you are on the order's page, you see the "min" and "max" amount possible to trade within their reserves, just after the deposit address:
Of course if you send more coins than "max", you will have to wait until eXch has enough reserves, but it's quite clear on the order's page, so you should not be surprised. In any case if it happens and you don't want to wait you can just take a refund of your deposit.
Why would you even send your coin when your desired coin that you want to receive has no reserve?
Because of this:
Yes, the site allows you to create an order when reserves are empty. If you do it, this order would then be placed in a waiting queue until eXch has sufficient liquidity to process it. (a refund is always possible if it's too long)
Some people just want their backorder to be executed once there are enough liquidity and are not in a hurry.
Alternatively, it's always possible to set an alert on the app to be notified of reserves status..
