Beginning in the 1990s, there was a massive change in the way the insurance industry approached injury claims. Their old mantra was "pay what you owe, nothing more, nothing less." Since then, their mantra has shifted to "fight everything."
If you submit $5,000 in medical bills and lost wages and ask for an evaluation and settlement offer, their first line of defense might be: "Your care shouldn't cost $5,000; we're only crediting $2,800 of it." They may argue that your doctor's bills were too high or suggest that a pre-existing condition, like arthritis, contributed to your need for care, rather than the car crash itself.
Insurance companies will often say anything to pick apart the presentation you make to them because their ultimate goal is to pay less—not to pay fair value.