Enter a reason for deleting this comment
Good on-page SEO is very important and everybody is aware of that. However sometimes even big websites commit mistakes, such as:
One that I discovered recently, that I didn't realize, was having more than one H1 tag on the page. My logo was actually an H1 tag with an image nested in it, which is fine, but shouldn't be that way across all pages. Additionally, I had headers in categories that were H2 and H3 tags which should have been an H1 tag and on those pages, the logo H1 tag should not be present.
Not optimizing your website for mobile traffic will probably be an optimization penalty soon enough. Right now Google isn't penalizing websites that aren't mobile friendly but they did do an update that favors responsive designs.
I guess you could look at it as a type of penalty since you won't be gaining as much in the rankings if you do an SEO campaign as if you would if your pages were mobile friendly
Google pushed this update out because now at least 40% of their traffic is coming from people on cell phones and tablets. And with the old style brick cell phone being discontinued almost everywhere, more people are prompted to purchase a smart phone or upgrade to one. And every smart phone I've seen has a full browser that you can use any search engine you'd like on it. And since Google owns Android, they are trying to corner the market on cell phone browsing because all Android phones have the Google search engine as a default. Can you even change the search engine on your cell phone if you have an android? Or is it hard coded and you MUST use it as the default search engine no matter what?
Another problem is dead links that are aimed at your 404 page. Sure it's good to have everything redirect to a 404 page and notify a person that the page is gone, but if you're getting traffic to it, you should leave the page. If you don't like the page and you want to remove it, why not just edit the text on it so it's more suitable for you. You can even type something up saying this page has been removed and here are some similar pages you may like. This way you don't piss off your visitors who came in to read a certain page
Yes, I agree with you. Mobile devices are becoming much more important than ever before and website designers need to make sites as mobile friendly as much as they work hard to make them user friendly.
I will add one more on page seo mistake...
Using irrelevant keywords
The keywords you are using on your website or web page should be related to your niche. If your website's niche is traveling to Himalayas, and you are using keywords related to crusing, you are doing it wrong way.
For a website on traveling to himalaways, you should use keywords like Everest, Annapurna, trekking, mountaineering etc. If you use the right keywords, you have high chances of getting indexed higher.
What do you mean keyword density, is it the number of keywords on a particular web page? I have read of keyword stuffing that it is not legitimate regarding search engines. Maybe too many keywords when uploading a new content will spoil the web page? Having duplicate contents on the site may ruin the SEO capability of the site with search engines because plagiarism is not tolerated in the internet.