It is a simple consideration that an investor should have alternative sources of income and also if you have extra money to invest then Bitcoin would be the best venture for you. Your objective is to hold Bitcoin and your effort to be long term is DCA or single investment. Bitcoin is only recommended for newbies who do not bear additional risk in DCA strategy. The review of discretionary income source that you mentioned is that it is a long term investment endeavor where an investor is looking for a great strategy for his future.
I agree with you if you want to be able to carry out investments well on Bitcoin then we must have some sources of income to be able to maintain the assets in the long run because if the income we have hanay enough for needs is certainly not possible to run the investment because it takes a time that is not a short time to produce profits from the investment.
When someone wants to survive in the long run, it will certainly be very good in using the DCA method because they can always buy consistently according to their abilities after fulfilling all the needs they need because it will be very unlikely to survive if the necessary needs have not been fulfilled properly.
I think this is quite clear, because if you think logically, how can someone who does not have discretionary income comfortably invest in bitcoin. Because the name of the investment will definitely be held in the long term, so it is certain that the money used must really use cold money. because if not, the first thing that might have an impact is that you will sell your bitcoin faster, which is caused by pressing needs. That is why investing in bitcoin is really required to use cold money or what is called discretionary income. Because it is useful for the smooth running of our investment in bitcoin. So if for example you don't have discretionary income, I think don't enter the realm of bitcoin investment yet. Because basically your money management, or your cash flow system is not yet qualified. So the first step you have to do is increase your sources of income so that you can have discretionary income to invest in bitcoin.