It's also important to emphasize that Bitcoin always exists as a set quantity. For example, if you buy 1 Bitcoin, it will always exist as 1 Bitcoin, but its value will fluctuate. It's crucial to make them understand that no one controls the price of Bitcoin - it's all about supply and demand.
By explaining these concepts to them, they will be less likely to regret their decision later or ask questions about a bear market.
For me this is essential, knowing what Bitcoin can offer me and secondary to that
is the investment aspect.
I would snobbishly only consider a person a true Bitcoiner when they have an interest
in Bitcoin other than its ROI or they have a long term outlook. I dont consider anyone
with a "get rich quick" or only interested in Bitcoins market value to be Bitcoiners.
The OP has only focussed on "The price" and "The market" and "Investment", Bitcoin has
a lot more to offer, its just a pity that it seems they are overlooked even when explaining
Bitcoin.