I know of a few business owners who handled the marketing of their businesses themselves instead of hiring someone to do it for them. On being asked "why?", the most common reason was that they wanted to save money. A few did mentioned that it was easier as they understood their own business better than any outsider could. It was not surprising that most failed in their objectives especially when it was related to online marketing.
The reason is very simple. Even though they understood their products and services that they were offering as well as the company's strengths and weaknesses, they did not have the required marketing experience. One good example is a restaurant in Kuala Lumpur, Malaysia where my sister used to work. They were really doing well and they decided to create a website (on my sister's advice). However their budget for the entire project was only RM400/ (around US$115). This was really sad considering the fact that they spent almost double on flowers every week. Show how much importance they gave to online marketing.
Take my advice. If you need to market your small business, get the professionals to help you, especially if it involves website design. You may very well want to consider a company that specialises in providing full-service website development and consulting services dedicated to small to medium-sized enterprises.