Failures due to creep deformation are pretty common in solder joints - driven by residual stresses created during assembly which persist over a long time, and e

Failures due to creep deformation are pretty common in solder joints - driven by residual stresses created during assembly which persist over a long time, and eventually lead to cracks forming (stress relief - but not so good for the connection). Usually not an issue at room temperature, but it can happen - solder has a low melting point. In the case of the observatory, the failure happened in zinc components, which has a fairly low melting point. Turbine blades are just one of the most extreme examples, it's really hard to make a metal that resists creep in that environment.