Obsessive designer? You may have noticed: icons made in Mac OS X 10.6 are often washed-out/lighter.
Normally we create .png files of each icon state, then drag them into Icon Composer. But, starting with 10.6, the colors would lighten unexpectedly. It wasn’t dramatic, but with certain icons (like the one below) it was totally noticeable. The source is on the left. See how the red is washed out in the final icon on the right?
via Panic Blog » Saving Icons for Snow Leopard.