Altcoins are the most volatile cryptocurrencies in the market right now, a coin can do 10x and then go on to loose 70% of that value within the period of a few months. So altcoins arent necessarily the best to hold over a long period of time, however there are some great coins that may not do big pumps so often but they have a better chance of retaining their high gains over a longer period of time.
BNB is one of such coins and it is one of the few altcoins that i consider ideal for a long term investment