The convenient usage of "Animation on x", such as this:

Rectangle { id: coloreditem
    SequentialAnimation on color {
        ColorAnimation { to: "yellow"; duration: 1000 }
        ColorAnimation { to: "blue"; duration: 1000 }
        ...
    }
}

may not be immediately apparent to someone aiming to use nested Animations, particularly where the parent can specify which is the target for the animation. In this case, the user is more likely attempt to try ColorAnimation on color {, find that it does not work, and manually specify each target+property for each ColorAnimation.