On-Page Optimization is the key foundation to getting Google to recognize your site as legitimate. Site without proper meta tags, site indexes and ALT tags for images, can cause Google to penalize your site. A large site can take a couple days to analyze and fix any bugs. While this is no way ensures good organic ranking, it is the cornerstone to developing a site that Google and other search engines consider legitimate and index accordingly.
Search engines do not like broken links. Your site should be periodically checked to make sure that the links to and from your site are valid. In cases where links have changed such as when the site is re-built care should be taken to make sure that the links are properly redirected. This can be done with a htacess file or most plugins have features that will do this automatically.
Proper Meta information:
While meta tags information does not ensure organic rankings link it once did, it is important to have the title tags, meta tags and descriptions that match the page content. The most important thing that search engines look for is the title tag. The tittle tag should be 50-60 characters in length and should be relevant to that pages content.
H1 tags are another factor in how search engines determine how to range a page. I have seen in many cases where there are multiple H1 tags on a page. Search engines will ignore the information completely and will not be found for those desired keywords. While H1 tags did not hold the value they once did, they are still an important factor, especially if they are not done correctly.
Site Load time:
A site that takes a long time to load can not only detract users from staying on your site but is a factor in Google on how legitimate it is. Making sure that images / code are optimized for load time is important for your site.
The better the user experience on a site will determine CTR (click through rate). A better CTR is accomplished by keeping people interested and moving through your site. Relevance to the user, content and design all play into keep the users from “jumping ship”. Another factor that falls into this category is relevant content. Content as they say still is king (as long as it is relevant to the site). A site that has relevant content will be seen as more credible than one that has little content or content that is not relevant to the messaging of the site.
It is still important to have quality links coming from higher ranked sites. Social media traffic and pages that have a higher page rank that are relevant remain a big factor in the search engines algorithm. Care should be ensured that these links are built up “naturally” as search engines will look for an influx of links and deducts for your sites relevance.