Too Long; Didn't Read
Despite being a statistical experiment, A/B testing is quite close to being a form of art. Its apparent simplicity is deceiving, as many variables should be taken into account. Being a professional in A/B testing requires seeing a big picture, which includes all aspects of the product subject to testing; technical issues that might affect different versions’ perception; real-life context of the experiment and many other factors that may have an unexpected influence on the test results. Moreover, understanding human nature and taking a critical approach to interpreting data no matter how good it looks at first sight is a must.