Why are other sell limit orders being filled before mine on exchanges like gdax? If I place a sell limit order for ETH/BTC for 4 ETH at 0.07086, when there’s currently only 0.5 ETH on it. It becomes 4.5 ETH total. Then I see it start flashing up and down, up to 10, or 20, then back down to 4.5. Multiple times. That means orders are being placed after mine that’s being sold at 0.07086 right? Why is mine not selling?


Another side question is, why are sell limit orders being filled at prices higher than market price? Why would people pay 0.0710 or more when there are sell orders much cheaper.
Look at the trade history on the right. Do you see any price other that the current ask and bid ? This means that orders with values other than 9000 and 8999.99 (to take the example below) are not filled, so those orders are getting canceled.

Keep in mind that this domain is heavily automated and most of the activity you see here is bots fighting each other. So this level of frequent adding/cancelling orders on the order book is quite normal.