Once an outcome is known, particularly an adverse one, it often appears more predictable than it was at the time. This is known as hindsight bias. It is a well-recognised cognitive bias in legal analysis, and it has a direct impact on how cases in aesthetic medicine are interpreted.

One of the most difficult positions an expert witness can find themselves in is this: you have completed your analysis, agreed a common approach with the opposing experts, and the results are not what your instructing party hoped for.