In as much as Bitcoin investment is concerned,it takes the strong hearted to invest in it,even when using the DCA method or otherwise because of the fear of the unknown about the market price and alot of risk involved in it ,when using DCA method, it helps you accumulate and manage your resources to constantly be in the market,since it does not have a fixed amount to buy, instead you buy what you can afford,DCA method remains the best method of accumulating if you choose to buy bit by bit no matter how little it might be,you keep growing.
Bitcoin investment is not as difficult as your narrative on the bolded part, honestly your narratives on that bolded part can pass a negative information and can be misleading especially to newbies coming in to the thread, it is lack of understanding that makes some people think that Bitcoin is for the strong hearted, Bitcoin investment to the best of my knowledge is very much simplify especially with idea of investing from our discretionary income, that is to say, you will first ensure that your basic needs are taken care of and use the left over cash to invest and I don't see it as a big deal, that your are investing in Bitcoin doesn't mean you will not take care of yourself and go for vacation.
What I feel Sonia was referring to as strong heart seems to be people with courage and determination, in this case, I agree with her because without that, you cannot succeed in Bitcoin investment. In other words, it takes some level of discipline to be able to follow the various methods of Bitcoin accumulation strategies, be it buying the dip or the DCA method. Anyone telling you that you can casually buy Bitcoin and HODL without planning and developing the appropriate mindset, the person is definitely not being serious. Bitcoin investment is a courageous task that one should make strong decision that is followed with the discipline to stick to that decision.
We are living in a time where there are many ways of wasting money be it in entertainment, funding a habit or chasing a hobby, there are many things that gives momentary gratification that one is constantly tempted to spend money on; it takes strong heart to resist them which is what Sonia might be implying or would have said.