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.
I believe that most people are simply not prepared to risk losing their money. You need to understand - for successful work in the crypto market, sufficient knowledge and experience are necessary. Therefore, without sufficient knowledge, many people are simply afraid to risk their money, but over time the number of investors will steadily increase.