I could be misinterpreting your statement, but let me give my own perspective.
As a doc who went through a recent health scare only to find out after a work up that my fears were unfounded, I can say I've never been so thankful in my life for my $16.5K/mo maxed out, tax free disability insurance policy when faced with possibly having to cash in on it early. Sure, these things are expensive but I always recommend young docs (especially ones with loans) and little retirement savings to max out disability insurance plans for at least the first half of their career. If something happens to you and you can't work, or can only work very little...it can be absolutely devastating to your quality of life, as well as to your financial assets. Something else that people don't tend to think about is the undue burden it can place on families and loved ones. Let's say you get cancer and would like the best care possible but aren't covered for MD Anderson...well that's something you can finance easily with a good disability policy. If you run through your assets and need the help of family and friends, they don't have to spend a dime in caring for you as your disability policy will pay for everything (if you have a good one). Family shouldn't have to worry about the financial stress that is easily incurred when taking care of sick loved ones. If something like that were to ever happen to me (God forbid), I want my family to be as stress free as possible where finances are concerned.
Sure, my disability policy is expensive...but it provides incredible peace of mind. I have some colleagues who don't believe in disability insurance and I just can't wrap my brain around their mindset. If they had a car accident on the way to work and suffered a debilitating back injury or paraplegia...their life is irrevocably turned upside down and they have little to no ability to recoup lost future income.
For residents, the best time to start your policy is while you are young and in residency. You don't have to take out much, but that's the only time they will do a health screening and examine you. You will always have the option later on of increasing your policy without having to repeat health screenings or blood work. It gets much more expensive the older you get. I was a few years older than my fellow residents and my policy was noticeably more expensive even though I was in very good health. Also, many times you can get a discounted rate while you are in residency. For myself, I took out a small amount in residency and had a low monthly premium and I upped it significantly (I think to 8-10K/mo initially) after residency. A few years later I maxed it out to 16.5 and have kept it ever since.