The three barriers to global harmonization of financial reporting standards are:

1. Different Legal Systems: Various countries have different legal frameworks that affect how financial reporting standards are applied, making harmonization difficult.
2. Cultural Differences: Accounting practices and objectives may differ due to unique cultural factors in different regions, leading to differing approaches to financial reporting.
3. Nationalism: Countries may be reluctant to adopt international standards due to a preference for their own national standards, driven by a desire to maintain sovereignty in financial regulation.