Quite simply there are millions of your potential clients who use the internet, whom you will not be able to reach by any other medium without spending a lot of money. There are 51.4 million internet users in the UK alone and 2.2 billion in the world as a whole (Find these statistics and more at Internet World Statistics). To reach an equivalent audience by other marketing means would be staggeringly expensive compared to the set-up and running costs of web site.
As you would expect the Internet population is generally well educated and affluent. They either own a computer or have access to one. In the UK, we have the highest per capita spend in the world, totalling £68.2 billion online in 2011. This continues to rise annually in spite of the recession (find these statistics at IMRG).
So a web site allows you to convey your products/services to the marketplace without the expense of salesmen, mailshots, leaflet printing etc. And access a wider client base without additional overheads, but reap the rewards that investment would have brought you.
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