Very very interesting topic. There are couples of factors that are responsible for this. Imagine a young graduate that picks a job when he was alone and before you know it, he begins to think that he should not be alone, he wants a partner before you say Jack, children start coming into the picture, extended family comes up also in between and the list of liabilities goes endless meanwhile, his income is still alone, fixed and he has not multiply it the way he had done to his liabilities. Then, as long as he/ she doesn’t think of multiplying his source of income but keep growing his expenditure that will result to the situation above.