Whatever your credit score, the number is critical. It's how banks, credit unions and even property management companies decide if you're creditworthy or not. Your past credit history is nearly 40 percent of your overall score. If it's negative and your credit score is on the south side of 610, it can be a formidable obstacle to hurdle and put a serious "dent" in your personal lifestyle. For most people maxed out credit card debt can be the damaging culprit, but not as bad as totally ignoring your debt or seeing a notice from collection agencies or a regular basis.