Final answer:
Richard Wagner's concept of the orchestra pit was adopted by Puccini to separate the orchestra from the visual performance and create a more immersive operatic experience.
Step-by-step explanation:
The concept developed by Richard Wagner that was borrowed by Giacomo Puccini was the use of the orchestra pit. Wagner, in his quest to separate the orchestral music from the action on stage and to enhance the audience's focus on the drama, conceived the idea of the orchestra pit. This innovation allowed for the music to support the performance in a way that seemed almost magical, without the distraction of seeing the musicians. Puccini, among other composers, adopted this theatrical feature to similarly enrich the operatic experience, wherein the orchestra pit helped to balance the sound between the singers' voices and the instrumental music.