Suggesting that the SP500 has a 12% average return is ludicrous. I don't know what Dave Ramsey is trying to push with that inflated number, but don't join his inaccuracy. 10% is the highest I would quote, and even that is not adjusted for inflation--if you use the CPI to adjust, even with all ITS bias, it still brings it down to 8%.

with an 8% return, a $2000 monthly investment over 15 years would get you to less than $700k

to get to $1M in 15 years, you'd need to invest $3k/month at that rate and that's a lot more than the median per capita income in my region.

I find this article irresponsible. I would have voiced this privately but Twitter is down and I don't see the private message option today.

Remember--the awesome part of investment is the gains over time, so this article should stress that, not the performance of the SP500

https://www.investopedia.com/ask/answers/042415/what-average-annual-return-sp-500.asp

https://www.fool.com/investing/how-to-invest/stocks/average-stock-market-return/