Usually they recommend you to diversify your investment, so you avoid losses.
But as a real approach, having $1.5k, would you invest in how many cryptocurrencies ?
What if I invest little by little, only in Bitcoin, would that work as well ?
Do you want to grow wealth or preserve wealth? Diversification is for preserving wealth.
And how to preserve wealth if not with smart investments. You can always buy gold and have nice stash of it, price can even rise a little, risk is low as it can be when you are buying a gold, but proportional to that gain can be very little or not at all, maybe you will have as much as you invested. With crypto you are holding much more on stake, risk is to hold you money in crypto that fluctuate, but with risks there is a greater profit. Diversifying is when you have your money in more than one thing, and everyone should diversify.