I personally think that POLO grew faster than they were able to keep up with. Hence the crazy slow transaction times when trying to make a couple of extra few bucks when trading. POLO still is the most user friendly in my opinion, and the ease of use makes it No.1.
But they will need to pick up the pace, because before long some other exchange will take it's place.
It's a Dog eats Dog world out there.
Legit Question Here: -> https://steemit.com/steem/@n0rd/poloniex-is-this-the-end