The problem with this line of thinking is that the Central Bank is continually confiscating part of our income through inflation. For middle class people, the effect of losing buying power year after year after year makes it nigh impossible to save very much. The government has under reported inflation for fifty years and people just don't realize that they are being hit by this hidden tax. When one couples this with the income the government outright confiscates, it's no wonder that people are left impoverished at the end of their lives.
Another classic problem is that retirement savings are meant to work through compound interest over a long period of time. Small investments at the beginning of a working career are not the same as small investments made at the end of a working career. In fact, not even very large investments (assuming such funds are available) make up for the 30-40 years of compound interest that has been missed. One cannot really start late and make up the difference.