There are more financial products out there than there are players in professional baseball. Many are good for our financial lives but some are bad.

The following products cause a false sense of security, zap money from our cashflow, or rob us of the ability to take care of ourselves. Instead of financial products that derail us on our journey to wealth we should be thinking about buying into mutual funds, saving accounts, paid for real estate, and other things that increase our net worth and don't keep us middle class.
 Financing Furniture
"90 days same as cash" is one of the common advertising lines from furniture and electronic stores. Clever financing options are designed to get you in the door, dangle the carrot in front of you, and close the sale by getting you to sign a contract that will convert into back-charged interest if not paid off by a certain date. I learned that if I could get the money together in 90 days, why wouldn't I wait 3 months and pay cash?
Car payments
The most expensive thing we buy other than a house is a vehicle. Gasoline, oil changes, and new tires increase the convenience of our freedom to hit the road whenever we want but also impact our wallet. Pack on the top of that a car payment and you will see an incredible amount of your monthly budget being eaten up by transportation. A $20,000 car financed at 3.99% for 60 months will charge you about $2,500 in interest.
Student Loans
You may not have started out in the Middle Class and hopefully your are making a good living in your choice of career. Even with a good income you are more likely to remain in the middle class when a chunk of your monthly cash-flow is used to make payments for a degree earned years ago. If you have student loans then it would behove you to have them paid off early to free up money to purchase other financial products like saving accounts or mutual funds.
Lottery tickets
Taking unrealistic chances for riches has never been a good financial plan. The chances of hitting the right numbers for the Mega-Million are 1 in 175,000,000. That's not a very promising statistic. I took my budgeted lottery money and spent it on something else - my Roth IRA. The statistic are really good that I will become a millionaire before I retire. I did the math.
Social Security
Kind of like the lottery but without the possibility of a windfall - a sense that eventually the money will come in and everything will be OK. People are more at ease about saving for their own retirement because we believe Social Security will be there if we don't have enough. Examine the Social Security statement you receive in the mail and consider how much the expected $1,900 or so will be worth when you reach age 65. Not much.
Too big of a house
There is an argument for renting over buying: Monthly rent is usually cheaper than having mortgage payment of the same amount because a renter doesn't have to deal with repairing appliances, replacing a roof, or paying a plumber to fix a leaky pipe. However, paid-for real estate is a great line item on any net worth statement. What can keep someone in the middle class is a house that is too big for their monthly budget. A good rule of thumb is to have a house payment that is no more than 25% of take-home pay, or 30-32% if taxes and insurance (escrow) is included. Anything more than that makes paying saving for retirement, college, even vacation much more difficult. It could greatly slow down building net worth.
Credit Scores
When was the last time YOU used your credit score? Never. The bank may have checked your score or an insurance agent but consumers do not use their scores. Credit score lending is a quick and easy way to evaluate your credit worthiness and determine the amount of money or the interest rate they will lend you. It's a loan officer's job to lend money, so you're already "in" when you walk in the door. So a credit score can qualify you for a good rate or DISQUALIFY YOU FROM THE BEST RATE.