I learn more by being wrong than by being right
When people praise my ideas it is nice to hear, but I don't learn anything. If people disagree, I learn. If they convince me, I am thankful and I change. If I believe I was correct, it means I didn't explain the idea well. Disagreement improves ideas.
Failures? No -- Learning Experiences
We scientists (and designers) learn from our failures. In fact, scientists seldom fail. Instead, they say "that didn't work. Time to try something new." I prefer never to talk of failure. Instead, I say "that was a valuable learning experience."