Their is an adage in my country which say; he who fail to plan, plan to fail.
When it comes to Bitcoin investment, having an emergency funds is a must, because without it, it's very likely that in the nearest future you will fall back to your investment anytime their is an emergency, so it's very necessary to have an emergency fund aside from your decretionary income, so as to be able to wether the storm if any emergencies arise.
An emergency fund is not necessary for Bitcoin investment. An emergency fund is necessary for long-term investment. When you say an emergency fund is necessary for Bitcoin investment, I am a little confused. An emergency fund is not very important to you when you are planning to invest or starting to invest. However, it is important to have an emergency fund plan at the beginning of the investment. You should not delay investing to prepare your emergency fund.
Start your investment with a reliable income or alternative income and plan for the long term. As part of the long-term plan, have an emergency fund, reserve fund or sufficient cash flow reserve. Be careful not to make your backup funds weak compared to your investments. Having a strong backup fund is more important than being aggressive in investing. It is harder to sustain an investment than to grow it. You need to focus more on investment defense. Incidentally, it is not necessary to prepare your emergency fund before investing, it is necessary to focus on emergency funds and other funds after starting to invest.