Good article in general, I have a small question:

"Let’s imagine we perform 100 tests on a website and, by running each test for 2 months, we have a large enough sample to achieve 80% power. 10 out of our 100 variants will be truly effective and we expect to detect 80%, or 8, of these true effects. If we use a p-value cutoff of 5% we also expect to see 5 false positives. So, on average, we will see 8+5 = 13 winning results from 100 A/B tests."

If we expect 10 truly effective tests and 5 false positives, we'd have 15 tests that rejected the null hypothesis of h_0=h_test. Taking power into account, shouldn't we see 15*0.8, 12 winning results from the results? I.e. wouldn't one of the false positives also have not-enough-power?