Although difficult to show using camera close-ups, the difference of a dirty record before washing and ultrasonic cleaning and after, can be really astounding. Scratches and other forms of permanent damage can never be repaired but the large amount of dirt/dust/alcohol/mold/etc. a vinyl record can gather over the years can very efficiently be removed with these techniques.
Here you can find some comparison examples of recordings using a low/mid/high budget set-up, cleaned beforehand or not, restored afterwards or not, using an algorithm to repair or not. The Soundcloud files alternate between these different instances.