Nintendo president Satoru Iwata has admitted that sales of Wii "stalled" because the company was "unable to continually release strong software" and "unable to show a new game to become 'the next thing'".
"With the price drop, sales returned to a certain level, but they just did not reach the level of last year around this time," he said. "We decided that it would be difficult to sell enough to recover from the poor performance of the first half of the year.
"In order to reach it [the 20 million units target], we will have to move quite a large quantity, but it's a figure we released after having felt the momentum returning."
Nintendo introduced the new Japanese Wii price point on 27th September, reducing the cost of the console by 5000 yen (£33 / 37). Sales did not initially appear to respond, but the launch of Wii Fit Plus had an impact, helping to effectively triple weekly hardware purchases in the month that followed.
In the US, NPD sales figures for October are not yet available, but the Wii sold 277,000 units in August prior to the price cut, and 462,000 in September, with the price on the other side of the pond also dropping on 27th September, from $249 to $199.