The old train set has endured heat, humidity, and the exigencies of storage since last Yule. Folks expect it to run as usual year after year. Consider the fact that most of the household Yule sets are pretty old. They have been handed down to another generation as a Yule tradition. Along with adorning the Tree, they've endured the play of children year after year.
Most people expect the trains to run well every year.
No thought is given to wear and tear, corrosion or problems of age and un-use. If even half of the families oiled their trains in the last decade, that is a high number. For most, the old train is run right out of storage, with nary a thought of maintenance or safety. Those involved in the train hobby know all too well how these old sets bristle with worn wires, bent track and motors in need of oil. When you take out your old train set this year, please take a moment to consider safety and maintenance.