How exactly do altcoins gain value? There are so many altcoins out there and honestly you can see connection among these in terms of the drop and rise of price.
They gain value through the standard of their altcoin but the drop and rise of bitcoin always affect them all all because bitcoin is the measurement of the success of all cryptocurrecy. But it doesn't mean that bitcoin will carry all the altcoins on success but the contribution of each altcoins also play a big part.