There are people who drop prices of alt.currencies intentionally. From what I remember seeing on exchanges, I can make real conclusion: somebody intentionally work on drooping prices, they even put big money in it.
Who else has noticed? Who are "they" and why they do this? Maybe ASIC owners?
it can be any speculant with lot of BTC;
or it can be just "us" - all wanting dump coin that we all know are quite uselessding ding ding
Miners only are making a profit if they are turning their alts into BTC, aka dumping. The amount of dumping of every alt exceeds the amount of speculators/investors willing to buy every day, which according to simple economics means prices will continue to plummet until the coin dies due to miner inactivity.
This isn't news to most miners, which is why they continue to dump further exacerbating the issue. Unfortunately every coin has bagholders who will try and buy at the "great low prices" the "stupid miners" keep selling at, until they eventually give up and cash out as well.
Can any of these alts buck the trend? Only DGC and WDC right now seem to have a shot at it with their respective community's support, but that still might not be enough to overcome the daily dumping.