The cars battery is essential for it starting. Dirty terminals can have detrimental effects on the batteries life. A weak battery can cause hard starting and force the car to use more of its alternator power. When the car runs it relies on the alternator to operate the electrical equipment and charge the battery. It is important for the terminals of the battery to be clean and free of any corrosion. If the terminals are clean and it is properly grounded, then your battery can last you more than its life expectancy.