Given a Competent School, for an Average Student, a standard of 90% or higher on tests is Reasonable

Let me begin with how the world's most important jobs demand perfection - imagine if a Doctor who did open heart surgery only had 85 out of 100 patients successfully survive and kill 15 people by accident. Whether because they failed to study, or because they made a mistake. Now this clearly seems horrible, in the NHS alone we have the 600 million patients treated, suppose we say an 80% "B" score is fine, that would mean 120 million patients unsuccessfully treated. Even a 10% difference would mean 60 million people affected. As you can see here, the impact with just a B or an A would be absolutely massive in the medical industry, therefore the 90% seems reasonable for a stringent job like the doctor. 

Even if we go down to the more common blue collar jobs, there are Retail salespersons, home health, general manager, fast food worker, and Cashiers. Think about what could happen if the Cashier or the fast food worker messed up their job. As you can see, the highest earning retailers earn up to 600 billion for Walmart, resulting in a massive 60 billion dollar shift if my standards change by a mere 10%, or even a 1% shift could mean a 6 billion dollar increase or decrease. The massive amount of money to be gained or lost means, even in a simple task like scanning products and answering questions correctly, should be done to near perfection, don't even mention 90%, maybe they have to get it to 99% to be acceptable. 

Or perhaps the most important test in the world, the Driving test. Cars are perhaps the most common quick method of transportation, I am sure almost nobody would debate that, especially cross cities or even cross country. With about 1.4 Billion drivers in the world, it is clear that the standards must be high, since even if only 10% were bad drivers, that would still be 0.14 billion people who could cause accidents or injuries. In the statistics, it says Japan and Germany, which both have strict requirements on acquiring a license, both have a road user death rate of 4.1 per 100,000 people, whereas South Korea has a staggering death rate of 9.8 per 100,000. Now this might be different from the topic of having more than 90% of the score, however, I would argue that the competent school should also have the competent test that readies you for all the scenarios. An "Average" ready driver who has thoroughly studied the test should be able to not only get 90% on the South Korean test, but also a 90% or higher on the Japanese driving test. If we go with S. Korea's standards, we can clearly see that out of 1.4 billion driver we would have 140000 deaths, while we cut that in half with the Japanese standards. As you can see, setting higher standards for yourself or for the test can clearly make a massive difference in the world.

When it comes to a competent school, if all the answers are given in lecture or in the textbook, there seems to be no reason to score low. It is all up to the person's efforts in order to memorize or understand the information. If every question can be answered simply by looking back on a certain page, it seems reasonable to me that this simple task should be done well. Setting a higher standard for yourself means you will likely score higher and become a better person. If I am happy with just an 80, I might score even lower next time since my new standard is just a B. Wouldn't this result in a slippery slope? Everyone wants to be the best person they can be - if they shoot for 100, they might get a 90. If I shoot for 90, I might get 80. So the standard shouldn't be arbitrarily low - the high score of 100 might be near impossible, but the 10% margin seems to be a reasonable loss to accept. 

Even in the most entry job levels, Indeed admits that for a professional profile, a GPA at or above 3.5 would be the best. That's at the AB threshold - right near the 90 range. As you can see, the standards of the world clearly show that the 90% or higher standard is reasonable for the "average person".

good job, you pointed out all the weakness of the argument. I concede to you.

5. John Mark Froiland & Frank C. Worrell, "Parental autonomy support, community feeling and student expectations as contributors to later achievement..."

6. School of Thought - Your Logical Fallacy Is, Slippery Slope Fallacy Overview

7. NSW Government Education Standards Authority, Australia, Performance Band Descriptions

8. "Aristotle" Quote, Head & Heart - not actually Aristotle, apparently. My apologies.

kwalala!