Anyone that has a minimal capital that he cannot have a discretionary income in which he can use to invest in bitcoin does not need to save for in other for him to have the money that he wants to use to buy bitcoin. This is because he cannot buy once and relax believing that he will make good profit from the little amount of bitcoin that he bought, and you are investing in a long term . He needs to continue buying regularly using DCA method in order to him to grow his bitcoin investment to a level. What that person needs to do is to look for another means of income, that he can use for his bitcoin investment and also for his emergency and reserve funds, why he uses his first job to take care of other important needs and expenses.
Apart from that I don't see how such person will be able to invest in bitcoin, because it will be a waste of time and like gambling because he is not prepared and does not have what it takes to start his bitcoin investment journey.
I think you are getting your explanation mixed up somewhere. There is no specific capital that one could to start a Bitcoin investment. Yes, people lump sum with a huge amount but they don't stop there. Consistency in accumulation makes a brighter portfolio that one can rely on for better times.
It doesn't matter when you buy what matters is if you will buy and won't procrastinate. Buy whenever you have the money if you are a business person but if you receive monthly income DCA throughout. You will be very happy if you stack your sats now and stay humble on your investment.