Some of the reasons are hacking and vulnerability of trading exchanges, rules and regulations from countries and the restriction of advertsement of ICO in social media, google and other platforms of the internet. This are the bad news bitcoin is facing right now that's why it's in a bearish cycle.
Could you believed that there are SCAM exchanges out there. not just Scam ICOs. some exchanges are Scam as well. running away with people details and using it to launch attack on accounts on the real exchanges. situation like this scare people away from trading.
alot of people are scared of investing as well due to the high rate of volatility.