When these pumps happen, volume flows in from other coins. BTC enter's the market buying at a inflated rate by these pumpers. They drop support, and coin goes even lower then it was before the pump. In essence pumps are a transfer of btc from alot of hands(traders) to very few hands(pumpers). You can't guess when they are going to exit, or coming in. Just when you think you found out the game they change it up, and you are left holding the bag. Just some wise words from some one who has been around.