Fret Overhang
Less is better
When refretting a bound fingerboard it's usually desirable to undercut the tang so the fret end overhangs the binding.
But, if the frets are undercut too far, the ends have a hard time staying tight against the binding:
See? I can stick a sheet of paper under the loose end:
And, a treble string can get caught there if it slides off the fingerboard:
A fret that catches a string like this will become even looser.
To minimize the loose overhang, I always try to undercut the frets as close to the binding as possible:
Keeping the tang cut close to the binding is especially important with wide or multiple fingerboard binding: