They do not want to invest their money simply because they do not believe in something that they cannot have a hard proof and they cannot have it physically. Cryptos are digital and it is difficult to persuade some maybe because it is not regulated by the government so they feel that there is no security at all.
many factors that prevent them from investing in ICO. well, maybe they see so many projects that fail, or become a scam, therefore they become afraid. or they see the price of the coin being dumped, and have acquaintances affected. they are all afraid of the risks.