Don't want your early retirement dreams broken? Break these habits. Source: 401(k)

If you want to retire early, there's a good chance that your success will come down to your habits -- and not just having good ones. It's just as important to recognize when you need to make changes, and when you need to break old habits that get in the way of your success. We asked three of our investment planning and retirement experts to talk about habits that get in the way of reaching that early-retirement goal, and here's what they came up with. 

Selena Maranjian: A key trait that helps many people achieve an early retirement is dedication. You can’t just save what seems like a lot of money and then hope for the best. You should be saving aggressively and investing effectively, but you also need to keep your spending under control.

Thus, along with regularly reviewing how much you’re socking away and how well your nest egg is growing, you need to regularly review your spending. Do so, and you might be surprised at how much more you can sock away, making an early retirement more possible.

For example, don’t assume that if you shopped around for car insurance, or home insurance, or even health insurance a bunch of years ago that the good deal you got is still a good deal and that you’re paying reasonable rates. Spend just an hour on insurance once a year, calling your insurers and competitors, and you could save several hundred dollars on some of your policies. You can save more by upping your deductible to a still-manageable level, or by switching to a different insurer whose pricing algorithms charge you lower premiums.

Review as many of your spending categories as possible. Cable companies collect hefty sums from millions of households each year -- spending $160 each month (which amounts to nearly $2,000 each year!) isn’t unusual. Ask yourself if you can spend less. A call to your cable company might get you a better deal just for asking. Otherwise, consider cutting the cord and relying on your mobile phone and streaming services for your telephone and TV needs. Save just $80 per month and you’re looking at nearly $1,000 in annual savings. Do you eat out once a week, spending perhaps $50 each time? That’s $2,600 per year. Dine out every other week and you might save $1,300.

Dan Caplinger: One habit that many Americans still have is to replace their car with a new vehicle every three years or so. In the past, making that decision was more of a necessity than a luxury, as vehicle quality was less reliable in the past and therefore replacing a vehicle even after a relatively short time was the best way to ensure that you'd never have to deal with major repairs. Now, though, quality has improved considerably, and it's easier for those who wish to keep their cars longer to do so.

The problem with replacing cars quickly is that every time you buy a new car, you suffer a huge dose of immediate depreciation as soon as you drive it off the lot. Admittedly, higher-quality vehicles hold their value better than their counterparts in the past, and so you can often get decent resale value when it comes time to trade in your three-year-old model for a brand-new replacement. Nevertheless, over the course of your lifetime, you can save tens of thousands of dollars simply by holding onto your vehicle an extra year or two each time you buy.

The money you don't spend on a car can go either toward other key expenses or toward your savings, compounding the long-term impact on your wealth and making it far easier to retire early if you wish.

Jason Hall: So you’re diligently putting money away for retirement every month. That's great! But if you’re putting it in a taxable investing account, you need to break that habit.

Taxes are an inevitability, but if you’re not using retirement accounts to defer (or with a Roth, completely eliminate) those taxes until retirement, then you’re definitely hurting your chance of retiring early.

By first maxing out the $18,000 you can put in your 401(k), and then the $5,500 you can put in a traditional or Roth IRA -- plus additional “catch-up” contributions for the 50-and-older club -- before contributing to a taxable account, you’ll defer the tax impact until you retire. If you can invest in a Roth IRA (check here for income limits), you’ll be able to create a stream of income in retirement that won't be subject to federal income tax.

Yes, eventually the tax man cometh. But smart tax planning will mean you never pay a penny more than you should, and the difference adds up over time. If you want to retire early, it would behoove you to develop smart tax management strategies. These tools will give you more money to work with and help to stretch your nest egg even further.