Is it possible that successful companies devote more resources to increase diversity? Implying that companies are more diverse because they are successful. What tests have been done to tease out which is the causal factor?
I think ou are onto something - business is difficult and even simply surviving is a challenge facing most enterprises. Thinking about diversity seems like a first-world problem and only really on the radar of companies who have a strong foothols in the market already.
That is exactly the case. Look at the companies that scream the loudest about diversity and have diversity internship programs(FB, MSFT, Google). Smaller companies do not have the budget to hire "diversity officers". They spend their budget hiring the best people they can find.