The recording cutter head forms a tangent with all parts of the record groove by moving across the disc in a straight line, whereas the reproducing pickup traverses it in an arc. The axis of motion of the stylus is thus different to that of the cutter over a large portion of the disc surface. This is lateral tracking error, which produces second harmonic and intermodulation distortion.
"I just wanted to let you know how INCREDIBLY happy I was with my recent order, including 4 reel-to-reel to CD and 3 LP to CD transfers. These reel-to-reel and LP originals were VERY OLD and of a quality I actually thought would be "unrestorable". I work in the "audio business" and would have made these transfers myself, but I no longer own any ..."