Here's why:
* His style was considered unconventional and experimental. He was a pioneer of Post-Impressionism, using bold colours, exaggerated brushstrokes, and emotional intensity, which was quite different from the popular art of the time.
* He was often seen as a troubled individual. Van Gogh struggled with mental illness, which affected his personal and professional relationships.
* His work was often rejected by critics and galleries. He experienced many rejections, which further added to his frustration and isolation.
It was only after his death that Van Gogh's genius began to be recognized. His work gained popularity and critical acclaim, and he is now considered one of the most influential and important artists of all time.