What is the best explanation of "debt-to-income" ratio?

A low debt to income ratio is a good balance in debt income and a high debt income ain't very good and is hard to live off of

A low debt-to-income ratio demonstrates a good balance between debt and income. Lenders like the number to be low because, according to studies of mortgage loans, borrowers with a lower debt-to-income ratio are more likely to successfully manage monthly debt payments.