I have written posts about how hard it is to reach people on Twitter and Facebook. And the lack of engagement (I hate the term btw I consider engagement an action taken online: Link Click, Comment, Like, Reply, ReTweet etc) due to the platforms inhibiting this. I have also blogged about how hard it is to have scale and reach on social media.
But I find immense value for the platforms as simple customer service, community building and listening tools. If you have customers who want to come and chat with you by all means why put barriers. And talking with 1% of your customers regularly is much more valuable than zero percent, and in fact can be quite profitable.
But you can't do this part time. You can't check in on Facebook once a day, add a post and leave for 24 hours. You can't respond or converse on Twitter once a day either. You will never have a community no matter how big or small. You will never keep people interested in you or looking for you if you are never there. This means content and persistence. It means having a thick skin and showing a human face for your brand.
It takes a lot of energy and effort to build an online community for your business. I created and manage one for a client and now are moving some of that burden in house. Took two years with no gimmicks but we did it. It was worth it. We have extended our reach and awareness dramatically to where now we can actual redirect some of my time to other areas of marketing to grow even bigger.
I tell clients it is worth it because you get a multitude of value back. Sales. Feedback. Engagement. Customer Loyalty. But it really needs to be done by someone who is part of your business. I would not out source the work to an agency unless there was complete buy-in and understanding of the product, brand and customers. The clients want an easy fix. Cut a check gain a community. It doesn't work that way. I also see many small businesses posting infrequently and see how little they gain. They might have a lot of fans or followers but they have no value if you don't give them anything to respond to.