Hand Painted Buttons
Even with the advent of complex automatic and semi-automatic drills, presses and lathes that came with the industrial revolution, there remained considerable manual input to the manufacture of small items such as buttons; we now expect thousands to millions to be spat out of fully automated machines with minimal human oversight. Even in the 20th century there were still large numbers of manual workers and artists involved. In 1931 the number of workers were estimated at less than 100; in 1937 at around 500.
Hand painted detailing was still occasionally to be found on Australian-made buttons into the 1950s and 1960s, but less often. I’m sure housewives no longer wished to remove buttons before washing, and the automatic washers would have have washed off painted details quickly.