To put it in layperson terms. Defragging a hard drive put thing a nice order so the system can find things faster. You have mechanical arm and disc moving around trying to find what it has been ask to find. If things are in order it's quicker. A SSD is electronic. No moving parts. A SSD doesn't care where things are or what order they are in. It just finds what it is requested to find instantly. Defragging is a process of reads and wrights. Unneeded reads and wrights could shorten the life of a SSD. As far as I know it would not improve the performance of a SSD. I know of no manufacture of SSD's that recommends defragging of a SSD.