Taking your question non-rhetorically: because the error bars are wider than 10%[eg, 0, which finds a floor of 4% for anything based on polls], so anything less

Taking your question non-rhetorically: because the error bars are wider than 10%[eg, 0, which finds a floor of 4% for anything based on polls], so anything less than that is consistent with p-hacking/random noise[eg see 1], and this is pervasive enough[2] that social science papers should be assumed garbage until proven otherwise. 0: http://slatestarcodex.com/2013/04/12/noisy-poll-results-and-reptilian-muslim-climatologists-from-mars/ http://slatestarcodex.com/2013/04/12/noisy-poll-results-and-... 1: https://www.explainxkcd.com/wiki/index.php/882:_Significant https://www.explainxkcd.com/wiki/index.php/882:_Significant 2: https://en.wikipedia.org/wiki/Replication_crisis https://en.wikipedia.org/wiki/Replication_crisis