I hate to say 'it depends' but it really depends on the sort of business that you're running and what you're trying to achieve Simply adding more friends/followers doesn't, imo, correlate to more business and perhaps you need a different approach or goals.
E-commerce stores know their customers E-mail addresses/names and can easily build a following of people interested in their products. From that, they can create special offers or articles that these people would be interested in.
A plumber can add his clients and invite them to tweet him if they want any advice.
A consultant can publish articles on their specialist subject and post links to his blog.
A law firm can write a weekly round up of cases relevant to their specialist subject and tweet these to other lawyers to ask for their comments.
I tend to view social media as a pub. You don't want to sit there shouting at everyone and asking strangers to be your friend; that's just weird. But, if you start to spark up a topical conversation that some or a majority of the pub are interested in, and what you are saying is valuable information then people will listen.
You'll only be annoying if you sit in the corner shouting "BE MY FRIEND, BE MY FRIEND!" - try being a bit more tactful - write things that you know certain individuals would be interested in, show them and see if you can gain some traction through retweets and sharing.
