Insurance companies are easy prey to being hated. I don't want to jump on the bandwagon. However, I think United Healthcare could deserve it.
United Healthcare refused to pay my doctor because there was a problem and the doctor was not able to bill them until just past 90 days. United Healthcare claimed that was too old and refused to pay. In contrast, the doctor tells me that Medicare allows them to bill for up to 1 year, which is more reasonable.
After that, I talked with my doctor about United Healthcare and got an earful. It seems that the doctor's office has to call because United Healthcare's website doesn't give complete information. Then when they call, United Healthcare transfers calls to India where the operators are of low quality and can't answer some question. I saw for myself how long it took for the Indian call center to answer. It would have been faster to walk to India (not quite!)