If work ethic is so strong, why do so many people decide not to do 3 Advanced Highers in S6? I'm sure that plenty of young people would be capable of doing so, but most of them choose to prioritise having a relaxing year. Which is a pity, as Advanced Highers are probably the best part of the secondary school system in Scotland, and actually provide a bit of a challenge, a bit of room for individual initiative. In my experience (talking about children with good academic potential) there is little if any challenge at primary school, there is little if any challenge in the early secondary years (after all, there are no exams to worry about), there's a degree of challenge working towards exams in the latter part of secondary, but it's a crappy learn the rules of the exam type challenge, rather than anything that is actually educational. And then a lot of children choose to have a relaxing year in S6. Children are capable of so much more.
Just as an example, I got to know a teenager from another country a while ago and discussed her school with her. She was 16 or maybe 17, still had a couple of years of school left, in a country where they start school later than in Scotland. She was learning English at school, but it was the school's second modern foreign language. The children were pretty much fluent in their first foreign language, and had history lessons in that foreign language. All the children in her year were sitting a Cambridge English exam at upper intermediate level (which is harder than what's done in a foreign language at Advanced Higher level in Scotland). She told me that her class had read a couple of full Shakespeare plays, Pride and Prejudice and lots of classic English poetry (she mentioned some poems by Byron as an example). Remember, this was their 2nd foreign language, but they had clearly done more in English literature than Scottish children do. Imagine what they're studying in their own language. This was in a grammar school type system, and I'm not suggesting that this would be suitable for everyone, but these are the children who are really capable and keen to learn. Those children are not catered for in Scotland. That girl was keen, buzzing, ambitious, confident, very hard-working - in fact she was doing more than was required of her by her school. And interestingly she said there were a lot of tests at school and those were oral, viva voce tests.