There are many things most likely to consider whenever you're investing money in crypto..
These are:
1. Volatility of the Market.
2. They don't have the knowledge about crypto.
3. Negative news that they see or hear in social media/TV Media.
4. They were scammed and afraid to invest again.
5. Threats of hackers in the internet.
But users can also protect their computer from hackers by using:
1. Virtual Private Network for Internet Protocol
2. MetaMask Wallet
3. Not saving any private keys in your PC.
Market volatility is a doubled edged sword. Maybe there are just people who just tend to better use the market for their benefit rather than increase their losses. Cryptocurrency is pretty easy to understand and I don't there isn't a single soul not willing to learn the means.