I came to understand that many people don't really know how to explain bitcoin investment to someone else, they only tell them that bitcoin is a cryptocurrency,an investment that can give them higher return when they invest in it.
To me that is not what you should be telling someone you want to convince to invest in bitcoin,you start by telling them how bitcoin came about,a breaf history of bitcoin,the person who created bitcoin,countries or nations that have adopted bitcoin as their alternative currency.
Further more tell them how bitcoin work,how secured it is,bitcoin store of value,it network and many more,tell them that bitcoin can be use as an alternative to fiat currencies or as an investment that you can buy through crypto exchanges,tell them it provides service like peer-to-peer transfers on a digital network that records and secure all transactions,the network use a blockchain  an open source program that chain transaction histories to prevent manipulation.
With all this explanation I believe that the person we be convince and we be willing to give it a try.