The fundamental difference in mindset between the human cultures and the orcish cultures is, the theory posits, is that humans existed in spaces to avoid predators, and orcs existed in spaces to defeat them. The result is that the orcs, generally tougher and with more stamina, are socially much less concerned with fear and exposing vulnerability. Orcish behaviour in most cultures is extremely comfortable with admitting ignorance - which is where a body of opinions about Orcs being dumb come from. After all, if you ask an Orc something and they don't understand you, or the question, they don't feel any problem going 'what?' or 'I don't know.' This is especially frustrating because orcish patience means they tend to be okay with re-explaining questions to one another, but also, common lacks for specific expressions of ignorance.
This also shows in Orcish pedagogy. Typically, human models of learning are language-based and then practice-confirmed. Students are expected to listen to how things are done and then execute on them. Orcish models of learning are instead much less timely - Orc students tend to just shadow someone expert doing something, and after watching enough to believe they understand how to do things, they try them. This also means Orcish methods tend towards lots of fail-safe designs; ie, 'can this project fail in some way that would hurt a person who didn't anticipate it' because those are easier to transmit to students. The result is that for almost all forms of 'unskilled' labor, hirers who take on Orcish workers will be surprised how expert those Orcs are in the job - not realising that the Orc wouldn't have applied for the job if they hadn't watched it a few times and worked out how they'd do it. Where this model of learning often fails is things like industrial process, where information is defined not by practical outcomes but by multi-step processes.
The result of this kind of thinking is that Orcs very commonly show up to try jobs that interest them at places like trainyards and steelworks, only to find that the types of learning they're used to aren't well-suited in a working environment. On the other hand, sometimes an Orc will take up a job that lets them observe a very complex project, and then slowly accumulate all the knowledge involved, which creates the strange situation where an Orc lumber-hauler suddenly one day reveals that they know how to manage the entire process of steel foundry manufacture and hand-temper the flux, but they've literally taken years to pick it up through very inefficient, very steady observation.
The general result is if you see an old Orc in any job that has any measure of complexity, that Orc knows more than you do.
