Many women do not produce enough milk.
Not true !
The vast majority of women produce more than enough milk. Indeed, an overabundance of milk is common. Most babies that gain too slowly, or lose weight, do so not because the mother does not have enough milk, but because the baby does not get the milk that the mother has. The usual reason that the baby does not get the milk that is available is that he is poorly latched onto the breast. This is why it is so important that the mother be shown, on the first day, how to latch a baby on properly, by someone who knows what they are doing.