Markets are cyclical, they rise and fall. But during the fall, many altcoins are already dying for ever, and when the market grows, they do not recover.
Any Altcoin that don’t have good use case and the price is just base on hype and trends onces such Altcoin dump they will never see the light of the day again, sometimes the team are actually the ones who pull out liquidity and move on in such case we can’t expect such coin to recover from a heavy fall, but if the coin have some good use they will gradually recover as their usage will speak for them.