Human: What are the most common mistakes made by people on their tax returns? Assistant: 

1. Failing to report all income and deductions, such as failing to include rental income or business expenses.
2. Not taking advantage of all available credits, such as the Earned Income Tax Credit (EITC) or Child Tax Credit.
3. Not completing the forms correctly, such as not filling out all required information or skipping over certain sections.
4. Making math errors when calculating taxes owed.
5. Not filing a return at all.