They likely wouldn't ever break in a meaningful way. Thing generally break because of imperfect human design and oversight. The eventual AI that will be developed will likely be much more capable of designing and maintaining the tools needed to do the space labor. It would be monitoring everything 24/7 and fixing problems (with advanced AI designed robotics) before they happen. It all depends on how quickly AI develops, but human labor is not going to be a big part of the sci fi future. In fact humans may not be a big part of it at all.