What does the phrase "to be in the red" mean?

The phrase "to be in the red" refers to a situation where a person or organization has negative financial balances, typically indicating that their expenses exceed their income. This idiomatic expression derives from traditional accounting practices where negative figures are often represented in red ink. Therefore, when a person is described as being "in the red," it means they are not only lacking sufficient funds but may also be facing financial difficulties or insolvency. This context is crucial because it highlights the importance of being aware of one's financial status—staying in the red can lead to more serious financial consequences. In contrast, the other options suggest conditions of financial stability or success, which do not align with the meaning of "in the red."