It erases the negative emotion from the memory. Usually it takes more than one time tapping on the feeling from the bad memory to fully erase it.
But it's not bandaiding it, it's literally erasing the emotion from the memory and that's why some bad memories hardly cross your mind and if it ever does, you can still remember the details of what happened, but don't feel any negative emotions from it anymore.
Try it. It really helped me. I like FasterEFT better than classic EFT.