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.
I agree successful bitcoin investing depends on how much you earn and hold. Investing only once month is not best way. Instead of this split your investments weekly to reduce risks. Divide your salary into parts. Bitcoin investment and emergency savings and family expenses. This helps you invest steadily buy bitcoin at lower prices and control spending and make wise decisions. By doing this you will maximize gains stay financially stable and accumulate bitcoin more effectively.
Depends on the volume you can accumulate since somehow lump sum strategy may work that way especially if you could able to acquire huge volume. But if you can only spend few bucks for acquiring for monthly basis then maybe you will not get the best result what you wanted. But if this is what those people could afford and just think about they are doing a savings with bitcoin then plan to make an action in span of 4 - 10 years then maybe this is still better than nothing. For sure there would be some changes will happen on financial side and there's a chance that people could earn big then for that situation they could just adjust their purchasing power then accumulate more bigger volume. Maybe just set aside thinking about other things and focus first on building up your bitcoin portfolio. Later on once you are already gaining decent volume then by that time you can take care of other things which is important to make your life became more sustainable.