I believe the reason why many cryptocurrencies trader cant HOLD for a long-term is because their perspective about cryptocurrencies to get a rich quick scheme (The inexperienced traders). We need to change our perspective first, just because cryptocurrencies have a high volatility doesn't mean it will make us rich (high risk = high reward).
If our perspective has been changed then we need to work on our trading emotion to make it easier for a long-term trade.