The single cutaway LP style guitar of the early 1950’s utilised a trapeze style bridge, combining the traditional jazz/archtop style tailpiece with a bar bridge that the strings were inserted through, this unit was quite quickly replaced by the stud/tailpiece bridge which remained the standard until it was replaced by the tune-o-matic bridge assembly that added a separate tailpiece to anchor the strings.
Overtime guitar luthiers and players realised that the single combined bridge and tailpiece stud unit was a much better transfer method of string energy into the body of the guitar, and consequently created a more resonant device than the tune-o-matic bridge.
The stud bridge however suffered from the inability to be able to intonate the strings properly due to its design style.