(....)
How can we better identify them? I hope everyone can make suggestions so that more people can learn from experience
You don't have to go that far on this one.
Buy Bitcoin, its network is secured and you don't have to wonder why people are always suggesting it to have. It's simple because it's the top and if you're looking for a security, check its history.
Nothing wrong with altcoins, I believe. It's just a simple high risk: high reward.
That's why people are very tempted to invest in random altcoins rather than Bitcoin because of the reward, which this reward is extremely high, there are a lot of altcoins that can be examples of this.
Yes, it's common to see altcoins and everyone do understand that it's a high risk - high reward type of investment. But if OP is for the security whether it's with its network and as an asset per se, Bitcoin is top notch and everyone knows that.
what @hugeblack said above me is a good strategy when investing in altcoins, identify the risks of each altcoin you want to invest and allocate a specific amount for that, don't go all in.
I agree of not going all in on it.
I've got mistake in the past that I've decided to go all in for a few projects and altcoins that I thought will rise in the future. But that didn't happened so a mistake that I'm learning and applying the lesson to myself now.