Maybe the most important source of feedback is what happens in production. It’s amazing the information you can get if you properly monitor and analyze the data. Continuous delivery gives more precise feedback from different sources, thanks to observing the impact of every realized change while improving traceability.
Federico Toledo is Co-founder and Director of the software testing company Abstracta. He holds a PhD in Computer Science from UCLM, Spain. With over 10 years of experience in performance engineering, he's helped many companies successfully improve application performance. He is dedicated to testing education, wrote one of the first books in Spanish on testing, and formed Abstracta Academy. He also hosts a podcast called Quality Sense where he interviews thought leaders in software testing. Follow him on Twitter: @fltoledo