He wasn't a quality artist, mediocre at best. His architectural paintings have lots of detail, but things like parallel lines in walls are off, and so is perspective.

His renderings of humans was terrible. You may see some landscapes or buildings, but never a portrait.

There was a time when learning to draw was a part of a well-rounded education, so having basic artistic skills wasn't unusual. Hitler's may have been slightly better than average, but he clearly didn't have the natural skill to be a professional.

Think of your school orchestra. The first chair players are probably pretty good. In a Band & Orchestra Competition, they could probably play a pretty impressive solo, but they are still a long ways from getting a chair in any major orchestra in the world. Thats the level that Hitler's art was at.

He failed already at the basics... most of his paintings look nicely but odd... and than you realize he had no idea about perspective, while trying to do realistics paintings.

Ironically, his paintings are probably seen and analyzed more than any of his colleagues'.

If I recall correctly he just cadged off others’ work. It was popular at the time for artists needing some cash to go on location and paint postcards of popular landmarks and sell them to tourists. Hitler simply bought these postcards and copied them into his own art so he wouldn’t have to go paint them himself. He had no real personal style, his work was very conventional.

They lack a human touch. They seem less like paintings done by someone who feels feelings and more like snapshots that just encapsulate the scenery and nothing else. There is no emotional aura.