As well written as your article may be and as much as you need to appeal to spiders when writing online content, your words still rely on a strong visual image to first catch someone's attention.
When it comes to news feeds, there's a lot of competition out there, even within a single feed or site. A person scanning a news feed glances images and headlines. As a result, the ones that stand out are the ones most likely to be read. Those which are read are also those which receive some sort of interaction in the form of comments, likes, shares, etc. Interactions can dramatically help organically make an article more popular. But in order for any of that to happen, your article first needs to be noticed. This is where a strong image can help your content stand out from the crowd.
Many small businesses quickly become discouraged after putting up a business page, sending out "Like" requests to everyone they know, posting diligently for a month, and seeing very little activity on their page. Years ago you could start a Facebook or Twitter account this way and reach lots of people organically (i.e. without paying). These days though, social media sites (like every other business) want to generate revenue.
In school they teach us grammar and proper English as a lesson and you're penalized if you don't know the correct rules. Time was, where in the real world you needed to know these rules in order to write a business letter, for example. This was the way throughout society for many years.
When it comes to social media there are those who post spontaneously and there are those who utilize a calendar of pre-planned posts. Larger organizations tend to use a calendar while individuals may be more inclined for spontaneity. Whichever method you use, you need to be sure that your content is relevant and interesting to your audience.
Web design may seem like a simple thing to tackle, especially for an experienced print designer who's accustomed to designing collateral for magazines or mailings. However, aside from trying to achieve an aesthetically pleasing layout, designing for the web and designing for print actually have very little in common.