Why did Jean-Auguste-Dominique Ingres leave no pupils who continued his artistic vision?

Jean-Auguste-Dominique Ingres left behind no pupils who continued his artistic vision primarily because his style had become increasingly antiquated by the mid-1860s.1

During this period, the art world shifted its focus toward contemporary life, with Realist artists replacing the traditional exploits of the ancients as the dominant theme in modern painting. While Ingres was surrounded by a group of fanatical devotees during his lifetime, none of them successfully sustained his specific approach to monumental history painting after his death.1

Although some late 19th-century artists, such as Edgar Degas and Pierre-Auguste Renoir, drew inspiration from his work, Ingres was not recognized as a major figure of early modern art until the early 20th century. At that time, his linear lyricism and anatomical adventurousness became significant touchstones for avant-garde masters like Pablo Picasso and Henri Matisse, rather than direct followers of his traditional Neoclassical style.1