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.
I think the summary of what I have understood so far is that the approach some newbies should really take is to emphasise the importance of taking healthy mindset actions and learning from others experiences and also learning to adapt to the market, rather than waiting for ideal conditions. The part you made mention of can still set up emergency funds after investing. I would say even if they don't have everything perfect from the start, in my own little understanding, they can still adjust, and then improvement takes place, plus improving their strategy changes over time.
If someone does not have a supply of emergency funds but has discretionary income then they should invest in a different strategy.
In each case, the type of investor and economic situation will be different so the solution strategy should be applied by considering the solution way separately.