Why do health insurance companies drop people who are sick?

And people who have preexisting health conditions? I read an article in a magazine about how a man who desperately needed surgery for his heart and he was denied the money for that surgery by several health insurance companies. Eventually, the money was raised through the help of friends, family, and strangers. But by then it was too late. He was dying and those health insurance companies denied him. Maybe if they had helped him he would still be alive today. I know it's all about money and business, but do health insurance companies really not give a f*ck about people? Why would they be so cruel and deny coverage to the people who need it the most?
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Well it is sad when people are denied coverage. Health insurance companies can not drop coverage due to health. As long as premiums are paid their health coverage will stay in force. Now for preexisting conditions they can sometimes deny coverage for a period of time, usually 6 months from the first day that coverage was in force. Now if you are already sick your not going to be able to get coverage. That would be like writing a Life insurance policy on someone that is already dead. But if the health reform gets passed he would have probably been denied care as well. That is how it is in the other countries that have government ran health care.
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