The Movable Middle is a concept developed by the MMA and Joel Rubinson in conjunction with Neustar.
A brand’s buyers can be split into three groups according to how often they choose the brand when they buy the category. People who choose the brand 9 or 10 times out of ten are 'High Loyals’, 2-8 times are the 'Movable Middle’, and 0-1 time are 'Low Unresponsives’.
The MMA has found that people in 'Movable Middle’ are highly responsive to advertising - they are open to buying the brand and just need a 'nudge’ via the salience/reminder effects of advertising. 'High Loyals’ are also very responsive, but their purchasing cannot be increased much because they buy the brand nearly every time. The 'Low Unreponsives’, however, rarely buy the brand and are hardly affected by its advertising.
The report includes a case study showing how a brand achieved a 50% higher media ROI by targeting the Movable Middle compared to targeting all category buyers, This strategy also turned out to be a highly effective strategy for increasing trial because it inevitably results in non-buyers who have a profile that’s similar to the Moveable Middle being exposed to advertising that motivates them.
To learn more about The Movable Middle, listen to this WARC podcast.
For a useful discussion about this topic, take a look at this LinkedIn post.