Something we occasionally notice while running creative tests is that legacy/historical creatives get most of the spend(and strong performance) because these have social proof(likes/comments/views) that FB tends to favor -> and in these cases, new creatives dont always perform well when benchmarked against 'control' creatives when we run creative tests(either multiple ads in a single ad set, or 5-6 different concepts in different ad sets).
when you're running your first round of tests how do you account for the fact that the older creatives are doing well mainly because of social proof? in other words, how do you avoid killing a potentially high-performance creative that may be starting slow just because it has no social proof?