That is why they are considered as alternative coins to Bitcoin because Bitcoin is more volatile than and has more longevity than them which makes it more like a stable asset in terms of existence in the digital finance ecosystem. Altcoins have less volatility this means they fluctuate less compared to Bitcoin. If they drop in price it may take longer for them to recover becuase they are less volatile. And they also depend on the influence of Bitcoin for them to also rise back up whenever Bitcoin starts increasing or breaks a new ATH.