Some of it is a B2B vs B2C difference.  A lot of the big apps we think of like Facebook and Google started as B2C.. where viral marking and word of mouth is what you need.<p>If your startup is some enterprise product that cost $1000 a month.. or a small business app that cost $100 a month.. you are unlikely to get word of mouth users, and need to actually go down the sales route in one way or another.