No. Of course not. You have to create and execute a marketing plan that works. It may include social media, but it certainly doesn't have to.
Many people are successful with social media. Most people are not. In fact, most people are simply consumers of social media as entertainment. So IF you have a strategy, you can can do very well. But you don't have to.
Too many people/companies do a half-baked job of social media marketing. They stop and start over and over. They create a blog with three posts and never get back to it. They're not writers and they shouldn't have gone that direction. They pay attention to Twitter and LinkedIn for awhile and then ignore it for awhile.
If you don't have a strategy, don't pretend you're doing "real" marketing on social media. It's better to spend $100/month on pay-per-click ads than to have a fractured, inconsistent social media presence.
Social Media Myth Two: Seek expert advice on how to use social media. Other than my advice in this blog post, please ignore all advice you read or hear about social media.
Why? Because you can't be someone else. When you hear a great story about a successful campaign, remember that someone else did that. You don't have their business, their list, their fans, their personality, their budget, their branding, . . . etc.
You need to develop your voice, your branding, your audience, and so forth. You need to be you. Social media can be a great tool for letting you shine in your own unique style. Slavishly copying the "wisdom" of others' success can only result in a faded copy of the original.
Social Media Reality: You need to be intentional. That means you need to consider 1) whether to use social media for marketing, and 2) how you will use it, if you decide to.
There are many, many options available today. In addition to the "old-school" social media such as Twitter, Facebook, and LinkedIn, you now have Pinterest, Snapchat, Imgur, and more. Don't look for a formula to adopt or an opportunity to jump in. Create your own branding. Create your own strategy.
You might not be successful. Or you might become the next big success story that everyone copies.
If you create a plan that can be executed and measured, your chances of success are very high. Without a plan, the chances of success are almost zero.