Sometimes marketers are too cool for their own good. When the healthiest of all social networks is abandoned as a marketing platform because brands don't find it cool enough, a serious re-examination of branding priorities is needed. The findings of the South African Social Media Landscape 2017 study, released this week by World Wide Worx and Ornico, showed that the only one of the major social media platforms that experienced a decline in use by major South African brands was LinkedIn.A survey among 116 of the country's biggest brands revealed that the proportion using LinkedIn, a social network for professionals, had declined from 70% last year to 63% this year.This pushed it into fourth place in the brand stakes, behind Facebook (91%), Twitter (88%) and YouTube (66%).story_article_left1LinkedIn only just managed to stay above the fastest-growing of the social platforms, Instagram, which rose from 42% in 2015 to 62% in 2016. Clearly, next year, Instagram will leap ahead of LinkedIn.The irony in these trends is that LinkedIn remains the surprise success story of social media in South Africa, with its user base rising healthily by 19% from 4.6 million in 2015 to 5.5 million this year.Globally, it has grown marginally more slowly, at 18%, to 450 million users. This puts it well ahead of Twitter globally, although it lags the latter in South Africa.The key to LinkedIn's growth - and the reason marketers should revise their take on the cool factor - is the flood of young professionals embracing the platform. The number of people giving their work status as "entry level" made for the fastest-growing segment on LinkedIn over the past year, rising 50% from just over one million to more than 1.5 million.This is a clear indication of the appeal of LinkedIn for job entrants and junior workers. The kids who have graduated from both youth-oriented networks and from school or university are now arriving en masse on LinkedIn.What an opportunity for marketers. What a shame the marketers are still stuck in the junior school mode of the revolting kids who will hang out only with other revolting kids, also known as the supposed "cool" crowd.story_article_right2In truth, these are the sheep who are led by the nose into the Next In Thing. As a result, they are oblivious to the Next Big Thing that can change their lives. Or, in the case of marketers, reinvigorate their return on investment.The clue to these admittedly rude assertions lies in another finding of the survey: that only 29% of marketers believe they have an effective presence on LinkedIn. It's not a difficult platform, but it does need focus.The inability of the brands to develop an effective strategy to leverage the platform points not only to lack of focus, but also lack of interest.There is little question that social media has come into its own in South Africa. It is regarded as an indispensable tool by marketers and politicians, artists and activists, reporters and media personalities.However, if marketers persist in focusing on the platforms and segments they regard as cool, much of the massive brand communications potential of social media will be lost.Goldstuck is the founder of World Wide Worx and editor-in-chief of Gadget.co.za. Follow him on Twitter and Instagram @art2gee..