Really, most cryptocurrencies have stagnated in growth lately, that's simply because the price of Bitcoin has gone down, especially after the major correction last week (which we still may be in the midst of). Looking at the "Satoshi" or Bitcoin price of Electroneum, when it hit $0.23 the price per unit in BTC was 0.00001358 (or 1358 Satoshis) (according to CoinMarketCap.com), whereas right now it is 0.00001108BTC (or 1108 Satoshi)/$0.13 per unit.

The day following Electroneum's all time high (Jan 7) it was at 0.00001100BTC (or 1100 satoshis) except it's value was five cents more at nearly $0.18.

Since almost every cryptocurrency is traded with Bitcoin, their price is based off of Bitcoin's price, so when the value of one Bitcoin goes down, the value of all coins goes down (of course you'll always see a couple outliers, but they nearly always go back down in a couple days).

Investing in coins that have good marketing, community and an actual benefit/product (use-case) are generally the safest. In those regards ETN looks alright. But, as always, you need to use your judgement and try to determine which coin is going to be the one most recently doubling in price and investing according. However, day-trading/frequently jumping between coins might be smart, yet very risky.

Lastly, don't forget that at some point every coin goes through a correction, what goes up, must come down. If it's a good coin (or your lucky) it'll land at a higher point than previously before.