When developing an interface, I used to be really attached to the visual part–perfect layout, distributed weight of objects, adequate alignments and counted pixels. I had been considered once an overly-meticulous designer, always checking thoroughly if the developer was implementing the project with a high fidelity to the delivered mockups. Until then, I thought this was enough to be a good professional–after all, Design should be all about visuals
This line of thought, established by previously working at companies where accepting crazy estimates was part of the job and the main goal was to please clients (the ones who were paying) made me forget what Design is really about: methodologies, tests and process. Following the latter vision makes you leave aside personal taste, opinions and assumptions to focus on metrics and the real client: the end user. Not always what we believe is the most pleasant look leads to the best results, and that starts to make sense when you have a logical explanation powered by metrics.