Every grantee and science group is different, and builds their boxes back in the States with varying levels of IT competence. Being a wizard in geothermal imaging doesn't mean you're a wizard in building Windows 10 boxes.

So there's all these varying groups (we support over 20 different science groups on our station alone) building their custom boxes on a variety of OS's and hardware to support all their strange sensors and equipment, and many of them are so specialized that no one is allowed to touch them. Nearly all science systems run Windows 7 or some flavor of Linux, and because there is literally YEARS of work leading up to one of these systems appearing on station, we are loath to touch them for fear of breaking some long-running or fragile science project.

In this situation I used my best judgement and determined that blocking Windows 10 would prevent more problems than it would cause for this group, and fortunately I was right.