The profile of Franklin Roosevelt found on the U.S. dime is believed to be based on a sculpture by Selma Burke. But the U.S. treasury credits the coin's design to former chief engraver at the U.S. Mint, John Sinnock. The question has stirred a bit of controversy. D.C. Sinnock was commissioned by Congress to design the dime after the death of Roosevelt. His design, which looked very similar to Burke's work, was approved in 1946.
Some people think the snub was racially motivated.
In other words, because Burke was African-American, recognition of her work was purposely excluded.