I was having a problem a few days ago where I would uninstall programs from my mac and none of that erased space would come back into available storage. I was freaking out thinking my Intel 320 was going crazy. I tried trimming, erasing free space, and other terminal commands. None of them brought me back the missing ~25gb of space that I was trying to get back. Luckily, user Matwue solved this troubling issue for me: So, if you have an SSD and are wondering where your precious GB are going, look no further than the stupidly made mobilebackups that are sure to be a headache for SSD users.