I'd expect the authors of the best business books (e.g. Andy Grove, Tony Hsieh) to have experience managing top corporations, or get paid to consult for managers of top corporations. Those are tasks that require intelligence and rationality to succeed at and consist of more than just motivating your workers. I'd expect that if there was no way to motivate workers in an intentional/systematic way, these smart, rational people would have said that in their books and it would be a truism in the business world. Instead, the truism is just the opposite.

I also think that things people take to be common sense should be given a strong prior in general. I see essentially no reason to believe that the threat of getting fired is the only thing that motivates anyone, so it's a bit frustrating to see you (apparently) privileging that hypothesis (because the great Eliezer, who has never managed anyone or worked at a for-profit corporation, suggested it?) when common sense holds the opposite.