Comment by robobo96

I agree. I work at a big insurance company with millions of online visitors each year. By A/B testing, we improve our services. A/B testing error messages has been a huge help for us. We can't ask users directly what they need: most users don't know what they need. That's why we do both qualitative (user research, online feedback forms) and quantitative (A/B testing, fake door testing, etc.) research.