You blamed the creative. It was the targeting.

You blamed the creative. It was the targeting.
The default conclusion is "the creative did not land", because creative is visible and targeting is abstract. Often it is the other way round.
How to tell them apart:
— Same creative, different audiences, results vary widely: targeting.
— Different creatives, same audience, all fail similarly: targeting or offer.
— One creative wildly outperforms inside the same audience: creative.
— Clicks are fine but nothing converts: the audience is curious but wrong, or the promise oversold.
— Nothing clicks at all: creative or placement.
The trap is that a wrong audience makes every creative look mediocre, so you keep producing new ones and keep confirming your theory. Meanwhile the variable you never changed is the one doing the damage.
Rule: change one layer at a time, and start with the layer you have examined least. That is usually not the creative, because creative is the fun part.
Test the boring variable first.