It’s become commonplace to beat up Silicon Valley companies for lack of diversity. Fear of PR repercussions probably had a lot to do with Google’s extreme response to James Damore’s internal memo.

There is a lot of emotion on both sides of this issue, but it is something that needs to be discussed.  I’d like to share my own perspective.

I have worked and managed in Silicon Valley for more than 40 years. I’ve worked at some of the best-known companies in the Valley, as well as a number of venture-funded startups. Throughout my career, affirmative action has been a major goal, and has become institutionalized in the culture and practices of most companies.

But after more than 40 years, efforts to increase diversity have not solved the problem. In fact, these efforts have barely moved the needle.

I was once congratulated by the HR department at Oracle, because my department had the best record in the company for “hiring, retaining, and promoting women.” Oddly enough, I pretty much ignored the affirmative action goals that I was given. I tried to hire the best people for the job, and then give them opportunities (and mentoring) to help them be successful in their jobs. I don’t recall ever taking into account supposedly gender-related factors in my management decisions.

And as it happened, that worked out pretty well. I had a great team… probably the best I’ve ever worked with.

But here’s the thing: when I exceeded the company goals for hiring and retaining women, it probably meant that another department failed to meet theirs. Or perhaps another company missed their targets. Because, at the end of the day, we were all hiring from the same pool.

Now, I understand that there are barriers to women and minorities in the workplace, and I am not dismissing them. Certainly there are some companies in Silicon Valley where discrimination and sexual harassment are egregious. But by and large, most companies try to do the right thing. And they have been trying for a long, long time.

It’s time to recognize the fact that this is a broad societal problem, and there is only so much that any company can do to solve it. Believe me, the biggest challenge in Silicon Valley has always been recruiting good people, and I think most managers don’t care anything about a person’s gender or race if they can get the job done.

We need more people in STEM fields, and that means we need to draw on a large and diverse pool. But it’s time to get real. Building that pool is not the sole responsibility of the companies that do the hiring.

40 years of affirmative action have not worked. Isn’t it time to look elsewhere for solutions?