What could prevent a motorised CD player drawer from opening after not being used for an extended period of time?
The grease on the pinion gear could have dried out or the bearing surfaces, usually plastic on plastic. There are things that could cause this that we may not think about, but if you have ever opened one of these up the motors are tiny and many are monitored or they open and close based on how much current is being drawn, two much current you hear them try to cycle but they cannot. A paper clip or large needle will usually release a stuck tray (small hole usually just under the tray that opens) manually opening the drawer can sometimes get them working again for a while.