I think it's pretty obvious when the buy not just altcoins but any other investments, that is when they are down. So in this case, if you look at most of the top 10 or top 20 altcoins, they are like down -30% to -40% of their previous all time high. So for me, take for example, ETH, they could still be a good buy at the start of this year. Because if by chance they reaches a new all time high, then most likely you will get a of profits. Just remember though that I said "chance" because we really don't know how the market will react, so there is still a risk even though we are still very much in the bull run or the altcoin market hasn't seen the bull run yet. So never ask for financial advise, because it might not be true at all and you should be the one deciding in the end.