Coins do not go up magically. There has to be an investment in cash for it to go up. Right now ETH is mostly sold als ICO compagnies need money to do whatever they told to do in the whitepaper or take a holiday. Futhermore some people just take the profit, as the orderbooks are not endless thick, every large sale just bumps the price a bit down. Not every downward wave is a signal for up. Sometimes down just means down 😉