It mainly depends on what you mean by "potential".
True potential requires real utility which altcoins lack. Take bitcoin for example. It has true potential because it has a real utility as "money" (store of value and medium of exchange). That is not true about altcoins. Majority of them were created to be pumped and dumped.
Inasmuch as altcoins are concerned, there is nothing like potentials in them since they cannot withstand long term volatility. We cannot call any altcoin as a potential coin since their volatility only last for a short interval of time. When we are talking about potentials we are making reference to coins that has the ability to survive the market in the long run. Even if there are new coins that can actually survive the market, identifying those coins is very complex so there isn't any need to even look for them in the first place except for someone who is just prepared to lose their time and money on them. Some persons go as far as investing in many altcoins with the idea that some of them will perform well during the alt season so imagine a situation whereby none of them could perform as expected isn't that gonno be a huge loss? so it is better to avoid them than to gamble on them and think that by investing in many of them it will be possible to make profits from some of them. Bitcoin is what we can ONLY call a potential coin because it can stand market volatility in the long run and for over a decade now it has really experienced exponential growth.
To recognize true potential in any altcoin you need to be an expert at a technical level to go through the project, check their paper, their protocol, look at the code, run their main client, etc. Something that most people are not capable of doing. But if you find one, then you are in for real treat (imagine finding bitcoin back in 2009).
Okay imagine the procedures in identifying a coin that can have long term value and it is even possible not to accurately identify the one with potential value after undergoing these many researches and all that. So it's just a kind of stressful mission to embark on and imagine if after doing every background checks and in the end you still invest in the wrong coin, the pain of the time you wasted while making those researches will be so annoying. Finding a real coin is not easy, imagine since 2009, out of the many coins that was introduced since then, only bitcoin has been able to maintain consistency in its price movement despite the many challenges that bitcoin encountered but it still stood strong and its becoming the world most valued asset.