As important as the design and the way a websites work, another important issue can actually have negative results on not only your customers but your business. Site speed is a very important topic and should not be overlooked when having your website designed or re-designed. It can actually directly hurt your sales and cut into your profits as people do not have the time to sit there and wait for your website to load. This is something that good sites take advantage of only having very small load times and bad sites seem to ignore(because they seem to overlook download time without even thinking of site optimization).
If it takes forever to get into your website as well as click through it(meaning it takes forever to load each page) then people are going to leave your site. Remember this. Just think if it takes you 20 minutes to walk to a grocery store or 5 minutes to walk to the local market(where you can get everything you need) why would you walk that extra 15 minutes? Simple, you just wouldn't walk that extra 15 minutes and this is true for a website. If I can get what you are giving me somewhere else then I am going to go there. If visitors leave then they do not get a chance to view your products, but, more importantly they will not purchase your products!
Site speed can and will lead to either more sales or less sales. Which one it is will determine how successful your website will be but also how long it will be around. Also you have to monitor competitors sites to see what their loads time are and try to match them. Start giving their customers a reason to come to your website. Combine quick load times with great products as well as great prices and your sales will start to sky rocket.
Remember to stay away from heavy graphical sites and try to use more text for area(html text not graphic text that is). This will improve performance but also will increase the click through rate of people viewing your website. The more pages they view the better your sales will be. Save your visitors alot of download time and this will give them a reason to visit your website, look around and will help increase your sales!