An attractive theme will have a good chance of giving a better impression on a first time visitor of a website. One of the greatest things about the Drupal CMS is that it can support any look you want it to in a just click of a button. Themes/designs are a very unique part of a web site. It has to be give a good impact.
The process of Theme Development involves briefing of design specification by the client. Once the layout is confirmed, the design is coded to XHTML/CSS, and finally the design is converted into an actual Drupal theme. This process ensures both that the original client specifications are met, and that the design results in a standards-compliant, cross-browser compatible theme.