Share your insights or perspective on the financial matter presented in the input.

Can saving/investing 15% of your income starting age 25, likely make you a millionaire?
Other people have already demonstrated the effect of compound interest to the question. I'd like to add a totally different perspective.  Note that the article says if you can follow this simple recipe throughout your working career, you will almost certainly beat out most professional investors [...] you'll likely accumulate enough savings to retire comfortably. (the latter point may be the more practical mark than the somewhat arbitrary million (rupees? dollars?) My point here is that the group of people who do put away a substantial fraction of their (lower) early wages and keep them invested for decades show (at least) two traits that will make a very substantial difference to the average (western) person. They may be correlated, though: people who are not tempted or able to resist the temptation to spend (almost) their whole income may be more likely to not touch their savings or investments. (In my country, people like to see themselves as "world champions in savings", but if you talk to people you find that many people talk about saving for the next holidays [as opposed to saving for retirement].) Also, if you get going this way long before you are able to retire you reach a relative level of independence that can give you a much better position in wage negotiations as you do not need to take the first badly paid job that comes along in order to survive but can afford to wait and look and negotiate for a better job.  Psychologically, it also seems to be easier to consistently keep the increase in your spending below the increase of your income than to reduce spending once you overspent. There are studies around that find homeowners on average substantially more wealthy than people who keep living in rental appartments (I'm mostly talking Germany, were renting is normal and does not imply poverty - but similar findings have also been described for the US) even though someone who'd take the additional money the homeowner put into their home over the rent and invested in other ways would have yielded more value than the home. The difference is largely attributed to the fact that buying and downpaying a home enforces low spending and saving, and it is found that after some decades of downpayment homeowners often go on to spend less than their socio-economic peers who rent. The group that is described in this question is one that does not even need the mental help of enforcing the savings. In addition, if this is not about the fixed million but about reaching a level of wealth that allows you to retire: people who have practised moderate spending habits as adults for decades are typically also much better able to get along with less in retirement than others who did went with a high consumption lifestyle instead (e.g. the homeowners again).  My estimate is that these effects compound in a way that is much more important than the "usual" compounding effect of interest - and even more if you look at interest vs. inflation, i.e. the buying power of your investment for everyday life.  Note that they also cause the group in question to be more resilient in case of a market crash than the average person with about no savings (note that market crashes lead to increased risk of job loss).  Slightly off topic: I do not know enough how difficult saving 50 USD out of 50 USD in Pakistan is - and thus cannot comment whether the savings effort called for in the paper is equivalent/higher/lower than what you achieve. I find that trying to keep to student life (i.e. spending that is within the means of a student) for the first professional years can help kick-starting a nest egg (European experience - again, not sure whether applicable in Pakistan).