But what I have always felt that is important to everyone (no matter your class), is the income you earn. If your income is good enough (assuming a monthly income), then you can choose to buy once and wait patiently till you receive the next salary before buying again.
I agree with you that the important thing in bitcoin investment is the amount of income you earn and also the amount of bitcoin you are able to accumulate from it, but the aspect of waiting to buy every month end may not be the best option or that is not a wise investment approach. For me if a person recieve salary it is not good to invest once every month but we can mitigate the opportunity by splitting it across the week. For example if a person recieve salary at the first month of resumption, he can fix on how to split his fund into the following part, 1 for bitcoin investment 2. For emergency 3. reserved fund to use for the purpose of family expenses and also for buying bitcoin every week(DCA), buy the dip and of course lump sum till the next month of his salary which is the 4th week to enable him accumulate bitcoin at ease, than investing agresively and sell later due to lack of proper planning. Sothat he can take advantage of buying the dip in some week from his reserved fund than just investing once in Bitcoin and using the remaining amount on feeding and or meceleneous expenses.