From time to time students report getting a question on the exam that they felt was not in scope for that exam, or not taught in the course.
Why was this question on the practice test/exam?
The nature of many vendor exams is that any service in the environment is in scope to be tested on any exam. However the reality is that for any exam (e.g. Architecture); some topics will be on the exam every time it is sat (Red), some will be seen frequently (Green), and some will be seen infrequently or only very superficially on that exam (dark Blue). I tend to visualize it as a circular bell curve or a dartboard.
Looking at the image below. Mastering the topics in each band as you go outwards from the core will achieve different results;
- Red and yellow are what will get you a basic pass with limited margin for error,
- Green and pale blue will get you a solid pass you can tell your friends about, and
- Mid and dark blue will get you a 90% or better, but will required personal commitment to research beyond the course.

If we then consider how this looks if you have the same scope, but think of multiple exams each testing a different area, you can see how what is an infrequent or a 'fringe topic' for one exam is a core topic for another exam.
If we consider the 'will appear infrequently' items from the discussion above (dark Blue) on one exam (e.g. Architecture). It is quite likely that it will be a core topic to another exam (e.g. Development)
Why was this not in the course?
If we tried to include everything that 'might' be on an exam, then we would have to teach 'everything' in the environment. While that sounds great initially, the implication is that the course would be 20 times as long, 20 times as expensive, and the core material that you need to pass any exam would be so diluted among all the other material that the probability of giving up or failing would be quite high.
Our approach is aligned to common teaching and certification strategy. To break the greater scope into sections and depth of knowledge and teach what is core to that aspect. Basically to focus on the core material that is needed to both pass that exam, and be competent, at that level.
If you are passionate about high scores (and bragging rights). In a number of articles, and the AWS prep course (opens in new tab), we recommend studying a number of courses before sitting any exams. This approach helps you to see a broader range of topic, and reinforces those that the vendor deems important and likely to be tested in multiple exams.
Note: We are always trying to provide the best balance to help students master the material and the exam. However sometimes we get it wrong, or miss content that needs adjusting when the exams change. Please let us know if you feel a questions is missing, or out of place, and we will assess it and try to bring the question set back into line with the strategy above.
If you need help, please contact Pluralsight Support.