Extended Shooting Time: The most significant benefit is having a fresh battery that will allow you to take more photos or videos on a single charge. This is especially important if you're planning an outing or event where you'll be using your camera a lot.
Reliable Performance: Over time, batteries lose their capacity to hold a charge. A new battery will ensure your camera has enough power to function properly and avoid unexpected shutdowns during use.
Versatility (for some options): Some replacement batteries may offer higher capacities (mAh) than the original. This can be advantageous if you want to extend your shooting time significantly.
Having a Spare: It's always a good idea to have a spare battery on hand, especially if you rely heavily on your camera. This way, you can avoid being caught without power in the middle of an important shoot.
Restores Original Camera Functionality: If your camera's performance has declined due to a weak battery, a replacement can restore its original functionality.