I am not sure if the results included in this thread for tested AVs are truly correct.
I repeated the test 25 times for Defender at default settings and the results were as follows:
12, 12, 12, 11, 10, 6, 9, 8, 7, 5, 7, 7, 7, 7, 3, 6, 7, 18, 17, 20, 16, 18, 20, 16, 16 ~ on average 11 vulnerables per 1 test.
So, it is possible that in a single test one could get the result 20 vulnerables and also 3 vulnerables.
To be sure, one should repeat the test several times for each AV.