Consider this example. Lets says your salary increases from $20,000 to $50,000 over a twenty year period. If inflation remains constant at roughly 2% per year, that amounts to 40% inflation over twenty years. That means that inflation eats out $20,000 of that salary and your purchasing power only increases to $30,000.
If you switched the model and made a great effort to earn as much as possible early in your life, things would work out better. If you saved and invested aggressively for a number of years however, you could use a compounding strategy to accelerate the growth of wealth.
Of course, not everyone has access to large sums of wealth early. However, nearly everyone can probably cut their costs. Cost-cutting is by the far the easiest way to build wealth as noted by Warren Buffet many times. Buffet purchased his house early in his life, because he knew that the savings on his house could be invested and compounded significantly over the course of his lifetime. For people interested in building their household wealth significantly, you should adopt this strategy as a matter of urgency.