I wrote an essay on this. And now I'm obsessed. Slight deviation from the anxious young women theme of previous lists. Will get back in brand soon. Suggestions welcome!
  1. It does not take into account income inequality.
  2. It entirely ignores sustainability, ecosystem value and damage being done to our environment.
  3. It ignores unpaid services including housework, childcare, etc.
    Resulting in many women who choose to live at home being seen as not contributing to their country's economy.
  4. If you choose to quit smoking or walk to work you are actively decreasing your country's national GDP.
  5. It does not account for subsistence economies.
  6. It ignores any source of pleasure that does not result in a monetary outcome.
    Religion, culture, etc.
  7. It results in complacency against poverty.
    As Africa's GDP increases many assume poverty reduces automatically. Whereas often those in need are actually losing money.
  8. Lots more reasons.