Some benefits of a process of continuous improvement vs. drastic periodic redesigns include: project cost reduction, conservation of past project investments, and gradual ease of longtime users into new UI and UX paradigms. The shorter 2-4 weeks cycles of a more agile approach to digital projects can help an organization keep more in touch with their audiences and stakeholders. The longer cycle (4-6 months?) of a drastic redesign risks being out of sync with changing user needs by the time the project is over. Shorter iterations allow more opportunities to communicate with key audiences and stakeholders. Short cycles can still be flexible and incorporate steps of a traditional waterfall process, just in a shorten time-frame. A web development process of continuous improvement better meets the needs of both clients and users than a traditional periodic redesign approach.
10 Harsh Truths About Corporate Websites. Smashing magazine. 2/10/2009.
Web Optimization: Redesign Out, Continuous Improvement In. CMS Wire. 4/25/2011.