I'm actually quite surprised that the PLEK machine doesn't do the polishing as well. Perhaps the makers felt it wasn't necessary?
I rather suspect that many guitar makers will use it, even for the high-end guitars, as it replaces the tedious process of getting the frets set correctly. For those higher-end guitars, a proper luthier will likely still do the final tweaks and polish.

An instrument with steel strings will gradually wear the frets, so they'll gradually go out of fettle as a matter of course. At what point that suggests a repeat process is probably personal preference.


Jazz relative beginner, starting at a much older age than was helpful.
AVL:MXE Linux; Windows 11
BIAB2025 Audiophile, a bunch of other software.
Kawai MP6, Ui24R, Focusrite Saffire Pro40 and Scarletts
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