I think you failed to understand that your discretionary income comes from your salary or from the money you make from your business. And I found this your comment above confusing, because I don't see any reason why you said that our discretionary income should be use to accumulate bitcoin, while our salary and money coming from our business should be used for settling our basic needs and expenses, and you forgot that our discretionary income from those two source. Instead say that will should only accumulate bitcoin with our discretionary income and not with money meant for settling our basic needs and expenses.
Let me rephrase what I was trying to say. We have a monthly income that comes from salary or through some kind of business. If we utilise that income for accumulating Bitcoins, then we might not maintain consistency in accumulating Bitcoins because salaries are not increased in accordance with inflation rate.
What we need is a constant stream of income that goes straight into Bitcoin and that stream can be income generated either from signature campaign or through some other part time job. In this way, our monthly income can be used for our daily living while the extra money we generate goes straight into accumulating Bitcoins. In this way we can maintain consistency in accumulating Bitcoins and also hold them for long duration like 10 years or more.
As long as you have a salary coming in, you can always remove your discretionary income out of it, but if the salary is small to the extent that you can't have a discretionary income after all basic needs have been met, then it's mandatory that you look for another source so as to have a discretionary income left after all expenses have been made, because it's only through your discretionary income you invest in bitcoin, if you don't have a discretionary income and you went ahead to invest with whatever funds in your hand, it's pure gambling that may likely not end well because when the needs for the funds used to invest arises, you are bound to sell prematurely even at a loss most times, so as to meet up to that pressing needs the money is meant for, so investment outside your discretionary income is not the best way to invest in bitcoin.