Do you want to turn more of your web visitors into customers? For example, if you have 1000 web visitors and 10 of them turn into customers you have a conversion rate of 1%.
Now imagine you have done some Pay-Per-Click advertising and you have increased your web visitors to 5000 and this has lead to 50 new customers. Then imagine you look at improving your conversion rates to 3%. Suddenly your same marketing budget and time means that you are getting 150 customers.
The improvements will benefit your business in the long term too. Once we have worked on this, you should benefit from these improvements for years to come.