A thought occurred to me today, catching up on the status of the ISS EVAs to replace the broken ammonia pump (sorry I know it's old
news, but I've been busy) that without the shuttle large pieces of broken hardware might collect around the station over time unless
missions are tasked to de-orbit them. And a destructive de-orbit of broken hardware will take the mysteries of their failure
with them.

Again, over time, the inability to return large objects via the shuttle will have an impact. Something to consider. Maybe the old
robotic Buran will see a comeback?

Dave