I'VE ALWAYS BEEN ATTRACTED to the pipes and wheels and dears of old machines so of course I discovered rust. Iron changes shape as it comes into contact with oxygen and in time completely disintegrates. Paint peels and bubbles before it comes off but meanwhile it looks great.
I'm not sure why rust seems to go with every other color, but it does — even orange. And people seem to understand that machines will decay looking good if they paint them with the brightest of primary colors.