The study looked at how big banks in Mexico hid risky loans before and after the financial crisis in the 1990s. They found that when big banks were sold to foreign companies and bailout money ran out, they finally admitted to having bad loans. Smaller banks, on the other hand, were more honest about their risky loans from the start. So, big banks used bailout money to cover up their bad loans, while smaller banks didn't need to do that.