Battery terminals can tenet more problems than just poor starting to the vehicle. The “blooming” corrosion taking place on the battery cable ends appearance is pretty extreme. But even minor corrosion can bring down alternator output by 30 percent. That can strain your charging system and cause early failures.
On the starting side of things, the extra resistance causes slower cranking, overheated starter motor windings, and premature starter failure. Prevent premature failures by replacing old corroded terminals. You just need a set of wrenches, a hacksaw, and about an hour. For more information read the article.