an altcoin that is not yet in the top 500, because it has the potential to make my $500 into $5k or even $50k, but of course the risk is definitely big (high risk, high profit) and altcoin that I recommend is UMB, because I see this project as a hidden gem, so when the right time comes, then the price will definitely increase very high, so of course UMB has a good potential to be used as a long-term investment and can make me rich, but if you want to invest in UMB, then I still advise you to DYOR before investing in UMB.
What are the odds of that happening? Don't you think that a cryptocurrency that has already earned its name and position in the market would be a better choice when making such a decision? Even if you decide to invest in a new coin or token, at least don't put all your eggs in one basket because if the token or coin fails and doesn't fulfil your expectations, all you can do then is regret your decision which is to no avail.
So, when you are investing in altcoins, you should always diversify the amount you are going to invest so that if some of the coins you've invested in fail to provide you with good returns, the others that work will have it covered and you will still do good and won't lose any money for the investments that failed.