Customer Who Was Right and I Was Too Proud to Admit It

Someone told me my product was confusing. I explained why they were wrong. Patiently. In detail.

They left.

A month later I watched someone else use the product and get stuck in the exact same place. The customer had been right. I had been defensive.

I've gotten better at this, but not perfect. The moment someone criticizes my work, there's a flash of resistance before the listening starts. The flash never goes away. I just try to make the listening faster.

How long does it take you to actually hear criticism? And has your pride ever cost you someone who was right?