Yeah, one of the main reasons people lose interest in Bitcoin investing is often because they have a mindset or are rooted in initial motivations that aren't solid enough. Most beginners are interested purely because when Bitcoin prices shoot up they hope to get rich quickly without understanding the basics of Bitcoin or having knowledge about the technology behind blockchain.
When the price of Bitcoin starts to go up, that is when a lot of people start picking up interest, and they forget that if you are doing DCA, then it is not really a problem, but people think it is only when the price is high that they start to pick up some interest in Bitcoin, and it does not work that way because it's called an investment there should be a target, and when the price shoots up they want to be part of does that are making profit and it does not work that way.
When the price suddenly plunges due to sharp volatility, what they feel is fear and they choose to give up rather than learn more deeply. Besides that other factors, like you said are that they start with money they aren't ready to lose, so they often need the money back and surely negative news about scams and lack of financial literacy also speed up the loss of interest. As a result, many people only see Bitcoin as speculative gambling even though behind its price fluctuations there are much more interesting benefits if explored with patience and the right understanding.
And even if you are starting with an amount of money you can lose, the issue is that they have a very unrealistic idea in their head. Instead of calming down, Bitcoin's volatility does not wait for anyone, and we have to know that there could be a change in price at any time, any day, so this is something we have to be prepared for so that we don't make mistakes. So we should know that not everyone is cut out for this because a lot of people are going to abandon ship for sure, and that is why you see that a lot of people keep selling, possibly because they could not keep up again.