Reason is that you don't know your enemy, because the person you think is your best friend that you can discuss your cryptocurrency investment can be the person that will gang up against you to bring you down or steal your cryptocurrency from you. If you can make your cryptocurrency investment secret, I think it will make you to live long to make income that will make the people living in your environment believe that there is a financial increase in you. Beginners need to take advice from this thread to know how to keep cryptocurrency secret not to expose themselves to their enemies, because you don't know who will be angry about your new investment.