Why did the Australians put the aboriginal "inventor" David Unaipon on their $50 bill?
He wasn't an inventor, but a spiritual motherfucker who wanted to invent a perpetuum mobile and anti-gravitation machine until his death.
The invention, the basis of modern mechanical sheep shears, was introduced without Unaipon receiving any financial return and, apart from a 1910 newspaper report acknowledging him as the inventor, he received no contemporary credit
When he "invented" it, there was already a big and successful Australian company that manufactured this sheep shearing machinery for 30 years en.wikipedia.org