Million-Dollar Mistakes in Index Fund Investing
Discover the critical mistakes investors make with index funds and learn how to avoid losing millions. This blog post will guide you towards a successful index fund investing strategy.
RETIREMENT & BEYONDAGE 20-30
Mr. Idiot
12/21/20242 min read


Hi, I am Mr. Idiot and I help people visualize their 'Financial Future' to inspire them for baby steps.
Who is the intended audience for this blog? Primary Audience : Any Age Mutual Fund investors
What is in this blog? This blog will show you how seemingly small differences in index fund fees can translate into a massive difference in your wealth over time.
Visualization Created for Megan & Chris : Megan and Chris both are 25 years old and decided to invest on S&P500 fund. Megan and Chris made the same smart choice: investing in the S&P 500. But Megan selected FXAIX (Fidelity), while Chris opted for BSPAX (iShares). The following table reveals the surprising impact of these seemingly minor differences in expense ratios on their investment outcomes.
With 13.09% return, Megan would have $1 billion+ and with 17.71% return Chris will have $789 millions dollars+ when both of them will be celebrating their 100th birthday. Chris would have 226 millions less compare to Megan.
The above table is the projection based on the assumption of last 10 years return of both funds.
I hope this visualization drives home the point that seemingly minor differences in fees between S&P 500 index funds can have a dramatic impact on your investment outcomes.
I invest with Fidelity. If you're interested in opening an account, please use the link below.




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Thank you and keep building your legacy through Generational Wealth! Take care and don't forget to enjoy the journey and take care of your health.
Note : Please note that the calculations are estimates based on certain assumptions, such as variable annual returns. This blog post is intended to illustrate the potential long-term benefits of consistent saving and investing, not to provide specific financial advice. The information presented on this blog, including any visualizations or projections based on average historical data, should not be considered financial advice. Investing involves inherent risks, and the value of investments can fluctuate significantly.


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