A lot of newbies in Bitcoin investment have made the mistake of buying Bitcoin when they have no emergency found or even not having a good stable income to hold Bitcoin comfortably without exchange them when they hard pressure.
I wouldn't consider it a mistake for newbies because even after buying without emergency funds set ups you can still set that up after having at least little to your portfolio while putting yourself to order, in my opinion some of this newbies that does this are opportunity grabbers which is even better than those who wait for the perfect timing which might not come, so I prefer they buy this bitcoin being imperfect and learn about things as time goes by than try to be all perfect set up all types of funds before ever getting to buy the real deal, bitcoin usually serve us opportunities like the little dips which a newbie could see and grab yet learn the who processes as time permits.
Yes, as a beginner, you'll inevitably make minor mistakes when investing in BTC, such as forgetting about an emergency fund, which is crucial. However, a beginner's willingness to invest in BTC is certainly a plus compared to not investing at all. And, of course, over time, beginners will learn from their experiences.
It's true that an emergency fund is the most important thing to prepare before buying BTC. However, if you've already bought BTC, there's no harm in trying to build one. Having an emergency fund will certainly give you peace of mind when investing in BTC for the long term.
And, of course, in my opinion, you don't need a stable income to invest in BTC. I believe delaying investing in BTC is a mistake, as its price will continue to rise. The most important thing is having money you can afford to lose that's worth using to buy BTC.