I think a lot of people, particularly those in business, think that it will be a huge time drain and that it will be boring. But the truth is you can do it quickly and it's actually a lot of fun.
You really "get" it when you experience it. Basically, if you can reach the point whereby you start to get some response to your tweets and updates while you're logged in there'll be no looking back. When this happens you get a real sense of contact with other humans. (And above all, social media is a human process. Unfortunately there's a widely held view that it's a technical, geeky thing.)
As those little notifications pop up you realize that those other users are sitting there at their laptops, or holding their iPhones. When they see you and your tweet, they respond. You can of course have actual conversations with these people in real time. These are great for building rapport and trust, and they do increase the odds that those followers will buy from you down the track.
But even if you don't have conversations, it's great when you see those notifications appearing before your eyes. This gives you momentum. It gives you a bit of a buzz, too. (Actually it probably means that you're addicted to social media! You're getting hooked on those little hits of dopamine ... Whether that's ultimately a bad thing or not I'm not entirely sure. Will have to take stock in another year or two I think!)
I've realized that you can get there quicker in some niches than others. For example, this point is easier to reach in a niche like politics. They're just more engaged. It can start to happen after a couple of thousand followers on Twitter. On the other hand, it's only just starting to happen on my blogging, marketing account. And that has nearly 4000 followers. Now it might take a bit more or less time and effort than that when you are in still other niches. But I'd say the more specific your field of interethe quicker it happens.
So my advice is make your social media participation regular, persistent. You don't have to spend hours at it every day, but you do have to keep chipping away relentlessly. You will reach a critical mass after which things get a lot easier. You feel like you're surfing a wave. You've got all this energy underneath and behind you.