It is true that the price of Bitcoin is uncertain in the short term. But considering this short-term uncertainty, calling long-term investments a test of luck is a completely different matter. If you want to make a quick profit by predicting the price of next week or month, then of course it can be like betting on uncertainty. But a person who continues to save slowly year after year with discretionary income after meeting his essential expenses is not actually basing his plan on the price forecast of next week. Rather, he is trying to strengthen his position in the long term. I am not saying that profits are guaranteed in long-term investments. There may be risks in long-term investments too, but that risk is not like betting on luck alone.