Cause and effect.
Games get pulled from the shelves because they aren't selling well anymore. That's the first step.
Of course from there, it spirals. Less shelf space means less sales, means less shelf space, means less sales. But if something just plain sells well, it will get reordered.
And of course, publishers or distributors can buy shelf space, but once again, they aren't going to buy shelf space unless they expect the units will move.
To some extent, you can create self-fulfilling prophesies, sure. But once you're past the launch, and talking in huge volumes like 1.5m and 3m, the difference in sales is going to come from the utility of the product more than anything.
"[Our former customers] are unable to find software which they WANT to play."
"The way to solve this problem lies in how to communicate what kind of games [they CAN play]."
Satoru Iwata, Nintendo President. Only slightly paraphrased.
