<b>I stacked two winners. They canceled out.</b>

<b>I stacked two winners. They canceled out.</b>

Rookie move, year three, still did it.

Test A: new headline, +12%. Test B (separate week): new hero image, +8%. Both clean wins.

So I shipped both together. Logic: 12 + 8 = a big number, right?

Wrong. Combined page performed WORSE than the original on either alone. The new headline promised speed; the new image showed a complex dashboard. They fought each other.

That's an interaction effect. Two elements that win solo can clash when combined because they tell different stories.

Now when I stack proven winners, I run ONE more confirmation test on the combo before trusting it.

— List your last two shipped winners
— Did you ever test them together?

Go verify your stacked winners actually still win combined. Report back.