I have this love/hate relationship with SATA hard disks. Today, my father had this problem again, of his PC not booting. It happens once every few months and the problem always has the same symptoms: the computer slowly crawls through the BIOS POST, has trouble detecting the hard drives, and then ultimately fails at the bootloader.
Every time, I keep telling (and showing) him, it's due to a loose contact in the SATA data cable and fixing the problem is as easy as shoving the plug properly back into it's socket. Yet, every time, I have to get involved in this.
What does that have to do with SATA? Well, first of all, I love SATA for it's slim data cables. Connecting the ribbon cables in the IDE days and arranging them to not block the airflow from the fans really was a pain in the behind. But unlike SATA plugs, ribbon plugs stay put! Hard drives, being mechanical devices, cause micro vibrations (and my father's Seagate seems to be exceptional good at that). Micro vibrations have a tendency to loosen connection assemblies.
I'm not really sure if SATA cable specification or the Seagate SATA socket is to blame for the constant connection loss, but I'm about to fix the problem for good with some hot glue.