One common failure of the original Oster blender

This is not a question, but a comment about one common failure in tbe 1980s. I found it in a workmate's blender who gave it to me to fix it. Then I found the same problem in my mother's own blender.

The symptom is basically that the blender motor does not operate. I opened tbe blender base and studied the wiring. I found the problem quickly. One of the solder points of the wire at the commutator contacts was open. Resoldering fixed the problem. So I believe that it was caused by some assembly employee doing a bad soldering job.