Nägele's art can be described as an artistic solo effort. With his pictorial poetry, he always manages to surprise the viewer; be it the pictorial content or the perspective he chooses. Nägele is attracted by the skeptical view behind the scenes, not the obvious, but the profound, the actually often bizarre or strange. Untouched by the broad art trends, he builds a very own visual world.
In terms of art politics, Nägele was very important as a member of the Stuttgart Secession. He was one of its leading figures and in 1924 significantly involved in the organization of the second exhibition of the Secession. His central role for the Stuttgart art scene is also evident in the large number of portraits that exist of him, for example, by Bernhard Pankok, Heinrich Altherr and Fritz Steisslinger.