Risk selection and uninsurance
For an intriguing answer to the question, does risk selection work to maximize profits in health insurance?, see Jason Shafrin's article.
For those too lazy to click-thru, the answer is yes, for the health plan.
Jason also has a related post on the dark side of risk selection, which is what happens to those risk selected against. In a word, the uninsured.
What's good for the company is bad for the economy.