So as long as you are investing what you can afford to put aside for a long term into Bitcoin, you are good to go through with Bitcoin volatilities because of the long-term perspective of the investor.
You are definitely correct, this is where most people make mistake. Knowing that bitcoin is something that has a value or has a way of growing over a long period of time, it is required to invest what you can afford to put aside for a long time. The challenge most people have with investing in Bitcoin is investing money they have need for urgently. This is not how investment in Bitcoin work because it will make you to panic in case price does not go your direction immediately.