"Shortages" are also the result of the high maintenance and neediness of the American public. In less affluent countries, you go to the doctor, get a diagnosis, receive a medication, then you go home. You get maybe 5 minutes with the doctor. The doctor won't hold your hand, spend 30 minutes discussing every detail you want to know, then jump through 10 hoops to convince you to take a medication with favorable risk versus benefit. They won't entertain the anecdotal concerns you have from reading webmd or the online help group on reddit. If you didn't have a disease, the doctor told you to go home and you do. The doctor doesn't sit there and listen to symptoms of the human condition for 50 minutes then offer no specific therapy.
The fact that seeing 18 patients in this country takes you the whole day (not to mention all the paperwork and unnecessary interfacing with the EMR) is a cosmic joke. If medicine made any sense at all, we would all be seeing 50/day and the shortages would disappear instantly.