"Hacking and scams remain the top risk for Bitcoin holders. Exchanges that shut down or passwords stolen from devices can easily wipe out a persons bitcoins. Moreover, governments and central banks from various countries are starting to impose limitations on the use of cryptocurrencies.
Digital coins clearly threaten the political and economic establishment, and the regulatory environment can quickly change with the stroke of a legislative pen. Banks and governments typically use familiar language in the media, such as the need to protect consumers from new risks.
We are hearing familiar talking points from politicians who are getting pressured from the banking lobby. It seems that the root cause of the status quos actions in 2017 is to protect fiat currencies and traditional financial interests. Competing digital coins represent a potential end to the governments monopoly of the monetary system." - Bitcoin.com
What are the top risks for Bitcoin holders?
My fear is that mining becomes centralized, after all, decentralization is what makes Bitcoin stronger than any other currency.
I think users have to become engaged in mining, so that we have a more distributed system.
Bitcoin volatility is one of the fear a bitcoin holder have, bitcoin prices changes as drop quickly. Most countries banned bitcoin so if bitcoin is banned in my country then there is no value of bitcoin I have. Bitcoin hacker and spam are also the risk for me as bitcoin holder. Also Bitcoins future is bright and this is confirmed that it will be soon applicable as payment and people will use it for invest and as currency.