Etymologically, the word fallacy means deception. In the field of logic, a fallacy is an argument that seems logical but is not. In the scientific field, fallacies may have their origin in technical limitations, methodological errors, prejudices, or cognitive biases.
The sniper’s fallacy is a famous example: a shooter fires several random shots at a barn; only later do they paint a bullseye around each of their shots. The conclusion on seeing the barn is that they are an excellent shooter, but the premise is false. This logical fallacy serves to illustrate that it is possible to relate different elements to reach the desired conclusion without this necessarily being true.