How would your family survive if you could not work and earn an income?
Income replacement coverage is just what the term implies, covering the future income, for those who are counting on it, family, business partners, creditors, etc.
However, the income replacement calculation can be tricky because of the need to calculate project into the future and make some assumptions about future projected earnings, inflation, changing financial obligations and other items.
Due to these variables, one could be looking at an increasing need, a decreasing need, or a static need. This must only be calculated with the help of an experienced, knowledgeable professional, as this calculation is too important to guess about.