That’s great to hear, but allow me to offer a common example. Ask a pianist to quickly play four octaves of melodic minor in thirds, and especially as one hand is ascending and the other is descending at the turning point, and there are two different modes being played simultaneously, many will indeed miss a note. Now make it a less common key, and you can see why it can be tricky for some. Certainly not everyone, for students yes and even some experience pianists may need to practice a bit first.

This kind of request is very common at many music schools for these kinds of exams.