https://poloniex.com/press-releases/2017.05.16-Industry-growth-and-its-effect-on-Poloniex/"We have never seen such enthusiasm for trading blockchain tokens as we have in the past few months. Since January, weve seen an increase of more than 600% active traders online and regularly process 640% more transactions than we did merely 4 months ago."
I am a newbie so what do I know but I also have a little experience with developing websites and this level of growth would be difficult to keep up with especially considering Ddos. I am reading that some of these attacks may be fake but even so I would imagine that they get many real attacks. I have experienced some lags and they are always irritating and sometimes an opportunity cost but still making money so I am not too unhappy about it. I am one of those 600% new traders.
Their site is laggy at times. I have been using it for a week now. It has happened a few times. Most likely it is due to a lot of traffic. Other than a few times, the other 50 or so times i was on and trading was fine. I go on it every few hours.