Mixing isn't the right word. Its more losing track of who owns what and who owes what. Then when they ask you to prove something such as if it was your business

Mixing isn't the right word. Its more losing track of who owns what and who owes what. Then when they ask you to prove something such as if it was your business taking the deduction, or if it was your business receiving the income, not you, then you can't. And then they get you.