I did some web searching to check your assertion. The key word above was "most," not all. So what are the cheap options? Condoms, spermicides, and The Pill. Condoms definitely break; better slather up some spermicide. There's an operator error factor in those. Will people do what's needed, reliably every time? The Pill has serious side effects. So the "ideology" could be that (1) the birth control should work, and (2) it shouldn't warp the person's health. In other words, you get what pay for, and not everyone can pay the same.
I did some web searching to check your assertion. The key word above was "most," not all. So what are the cheap options? Condoms, spermicides, and The Pill. Condoms definitely break; better slather up some spermicide. There's an operator error factor in those. Will people do what's needed, reliably every time? The Pill has serious side effects. So the "ideology" could be that (1) the birth control should work, and (2) it shouldn't warp the person's health. In other words, you get what pay for, and not everyone can pay the same.