Basically any transactions you do happen in the current block, and are confirmed in the next block. This means if you send MEOW to a friend in block 10,003 then it won't be "official" until block 10,004 has been written (and propagated across the network i.e. X confirmations). If a multipool comes in while diff is low (which they tend to do) they "trick" the algorithm that calculates the next difficulty rating (for MEOW this happens every 120 blocks right now) and make it super high. The multipool leaves, the diff is high, and instead of the ideal time of 30 seconds (for MEOW) per block, it sets up to be much longer (maybe 10+ minutes). If your interaction with the system happens during these "slow block" periods then you get stuck waiting for blocks to be solved before your transfer is official.