This is based on personal observation and studies of the altcoin market of a period of 2017/22
Altcoins are said to be the alternative cryptocurrency aside from Bitcoin and many of the altcoins are decentralized and also centralized, unlike Bitcoin which is highly decentralized and out of the control of anyone be it the developer or government Bitcoin has a total circulating supply. But Altcoin is developed by individuals e.g Vitalik Buterin Ethereum developer and teams members who are known in the society and the source codes of the coin can easily be updated which have made them not to have a static circulating which is has been the major reason why the altcoin market is hard to speculate because it circulating supply can easily be tempered more coin being minted at will which will render speculators analysis inaccurate in most cases.
It is safe to say that 99% of altcoins are created for speculation and have only financial interest. A group of developers creates some project on a wave of hype, hoping to make quick money on the altcoin industry. That is why we see how altcoins rise in price very quickly (making x100-x1000) and also fall quickly. Sometimes after they fall, they don't grow anymore, as developers start to create a new project that meets new market interests. Let's say that altcoins are not good for long term investments, because they are centralized, prone to hacks, lose relevance, etc. Only a small percentage of altcoins have long-term goals.