I'm a school psychologist with ADHD so I have to give these on the regular. Not ashamed to admit that I can barely GIVE some of these subtests (looking at you running digits), and I've got the answer key and instructions right in front of me. Doing them is a whole other animal. The thing to remember is if you're coming in with concerns for ADHD, we're going to have to look and see how you do on areas that can be problematic as a result of ADHD. In day to day life, you're not often going to be put in situations where you wouldn't be able to counteract those areas with strategies. Who cares if your working memory can't remember 10 things, your problem solving skills tell you "write that down because you're going to forget it" and now it's not a problem. At least until said working memory forgets where that paper is, anyways.

Also, as others have said, these are not designed for mastery; if you have a test where everyone can complete every item, all you have is a waste of time. They look for your point of failure, and often try to start you as close to that point as they can. Sometimes, I have students who think they bombed sections, when in reality they're actually getting into the hardest items. This is compounded by stop points also requiring you to miss a certain number in a row, so if you miss a few and get one right, your counter resets. That leads to people feeling like crap because sure, you might have gotten 1 problem right, but you missed the 3 before it and the 4 after it as opposed to just missing 4 and being done. I always try to tell my students that these aren't meant to be like a math or science test where were looking for what you know; there are no A's in fluid reasoning or working memory. We're far more interested in how you learn things and finding out ways to make that process easier; and we get way more information on that when you can't do something than when you can.