I did a bit of searching and found it here on Western Digital's website-
http://www.wdc.com/en/products/resources/drivecompatibility/...eSATA cables and connectors are designed for 5000 insertion and removal cycles while internal SATA cables and connectors are designed for only 50 insertion and removal cycles.
While that is what the spec intends, it's entirely possible to exceed this spec and I have to believe that Blackmagic has done their homework on this and chose a robust SATA connector for their cameras. I also stand by the statement that there has to be someone who has swapped their drive in and out 50 times already with no fail. I've only seen one report of a failed SATA connector on the BMCC and it was one in which the entire connector came dislodged from the SSD chamber.
Furthermore, I'll again cite my experience with the technology- I work on computer hardware every day and have worked with motherboards, drives, and SATA cables that have likely been through hundreds of connection cycles with no fail. I even have an Icy Dock hot swappable housing that has had at least that many swaps and no issue.
This is a good discussion but I don't think this is a concern anyone should have with the camera unless, of course, the ports start to fail.