Flash is used in web site design to give the presentation more presence and projects a truly interactive feel which should make them stand out from other websites.

Flash Website Design Misconceptions

A website with too much flash can be overbearing and impair the overall user experience in terms of functionality and simple navigation. Incorrect implementation of flash can also remove chances of the website ranking for targeted keywords.

Professional design teams will go to great lengths to deliver a website that looks outstanding, but this should not be at the cost of its marketing capability.