Sony fell short purposly on this.
They all do. Every major console launch for at least the past three generations has intentionally involved shipping a small number of consoles to artificially increase demand. There were a bunch of articles about it when the 360 was launched.
Even the Xbox360 launch was pretty low key...
That's not due to a lack of trying. That's just because shipping a small number of consoles wasn't enough to make them seem sufficiently desirable.