That is not a true statement. If a company's revenues are growing, the amount of debt they are holding can increase over time and they can be perfectly capable of servicing that debt in perpetuity as long as the cost of the debt isn't growing faster than the revenues. Revenues can grow both because of real growth (in the company's market or in the economy, depending on whether we are speaking within or without the analogy) and because of inflation (especially if the inflation rate is greater than the interest rate on the loans, which I believe is the case with some government debt).