Your website is like most things in your business, over time it becomes jaded looking. It does not have the same impact as it first had. This has a significant effect on your business.
Your website is the first experience many people have of your business.
Here are a few questions to consider:
Does your website look dated, uncared for?
A website designed over 3 years ago is likely to look dated now.
Is your website falling in the Google search results?
Google have changed how they rank websites and this effects your position in the search results. If your website is over 2 years old, it probably is not ticking the boxes for first page ranking.