I hear more and more about the dynamic side of search engine optimization: meaning you should optimize all the time, not like it was years ago: You do on-site optimization, forget about your site and watch traffic grow. Do you think that adding links constantly / non-stop, adding content on a regular basis serve as a separate factor Google and other SEs take into account?
On-page optimization requires changes every now and then, if you stay on top of the SEO game this is not a problem. Actually it's the off-page optimization people fail on, what happens is people achieve a ranking or position and effectively stop doing what they usual do and work on something else. You should set a dedicated amount of time per week on each website you own.
Yep! adding content and building links on regular basis helps you to improve rankings and to maintain em. It's a never ending process.....phew!!