It is not Content, or Design, but both.
These are not mutually exclusive but work with each other to produce readable content of value to the reader.
Design includes contextual imagery, headlines and subheads that ensure visual hierarchy and readability, pull quotes and images that break the rhythm, drop caps that capture attention, etc.
A great example of good blog design would be:
a] Think With Google [check this blog: https://www.thinkwithgoogle.com/marketing-resources/experience-design/mobile-shopping-ecosystem/]
b] Another would be the long form articles at The Verge [check this one: https://www.theverge.com/transportation/2017/12/12/16651026/faraday-future-investigation-money-debt-finances-yueting]
Content has to spell value to the reader and for stickability. Design eggs the reader to stay on and read - maximizes the value.
Content is most important, while you cannot ignore design as well.
SEO is how customers arrive at your online doorstep. To have a better SEO, you need to have a better content strategy in your blog.
Well, there is no quick and dirty answer. First of all, most everyone will say content. Some will say design, but I say it's content, audience, message, and design.
To the casual visitor, the design might catch their eye, but to get a return visit, the content had better be engaging, resonate with your target audience (notice I said target). I know of many bloggers that have little to no design for their blogs and have hundreds of thousands of subscribers.
So, if you are new to blogging, start with the audience and figure out to whom you are addressing. Learn what makes them hurt, stay up at night or just plain sick. Address those issues with viable solutions and live in their skin for a while. Your message will resonate with them if you speak to them, not at them.
Worry about design last. Just make it readable, visible or audible.
The short and hands-down answer? CONTENT. Remember as well, the title of your post is your "10-second elevator pitch" equivalent but you have a mere instant (pretty much) when it comes to online articles/blog posts to get them to read or pass. #technoage #nopatience #shortattentionspan
Yes, adding some user-friendly enhancements would also be great but that's AFTER you've got great content going on :)
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