Household income of 100,000 (higher than typical) gives 15K per year, or 1250 a month. 8% interest gets you to $376,000 after 14 years. No where near millionaire status. And this is assuming a tax differed investment path such as 401(k), and you still owe taxes out of that when you withdraw (assume 20% for fed/state, if you don't draw it out all at once, gives you around $300k).
Of course, add another decade and you are at millionaire status. Or don't contribute any additional funds, and wait 12 years, and you hit millionaire.
Yeah the numbers there don't add up as their savings plan changes once people pay off their mortgage, have a rainy day fund and have the kids education fund ready.They tell people to max out savings at that point. So it's starts out at 15% but ends up being much higher.
Of course, add another decade and you are at millionaire status. Or don't contribute any additional funds, and wait 12 years, and you hit millionaire.