And many others. WMRA's Martha Woodroof meets Danny Dolinger, who repairs stringed instruments for a living. When Danny (AKA "Fret Boss") bought his first good guitar (a Stratocaster), he took it apart the same day.
Even factory instruments, (says Danny's website) benefit from tweaking the parts to suit the individual performer. Regular usage wears down certain parts, leading to "fret buzz or dead notes" which can be machined-out.