My reason for failing to fill my most recent prescription was something hinted at by others in this forum, and similar to henryegan's: my doctor didn't discuss the medication with me AT ALL. I received a scrip in the mail with my lab paperwork. I am 26 and my cholesterol is 228 (which is borderline) and I was mailed a prescription for Lipitor.
I thought about filling it for about thirty seconds and that was it. I am not obese or elderly or otherwise resistant to lifestyle change, so I started exercising four times a week, eating oatmeal, tofu, greens, etc. Later I found out the ridiculous side effects and heard a few horror stories on Lipitor, including the fact that it's the #1 prescribed drug in America - no doubt because of scrip-happy doctors like mine. One of the side effects is digestive problems, and this doctor has written me previous prescriptions for already-bad digestive problems. What was she thinking?
If my doctor had even given me a phone call before prescribing me this drug, which I found totally inappropriate after some research, I would have considered filling it for longer than thirty seconds. As it was, I disobeyed. And I bet I'm healthier for it already. (I haven't had follow-up blood testing yet.)
When I have medical problems, I like to explain them to my doctor and ask for a solution. If that solution is a drug, great, but I'm going to ask for a lot of information before I commit to taking it every day. Does that make me a troublesome patient? I think disobeying the Lipitor was in my own best interests, but I certainly wasn't going to ask such a careless doctor for more advice on it.
I think the reason the article failed to come up with a good solid reason behind this is that there is no one reason. Some patients are forgetful, some are defiant, some are poorly educated, some are too well educated and think they know more than the MD, some have crappy doctors, some are strapped for cash, and some are like me and just choose a less expensive and more appropriate path.