A quality website is clean, well-organized, easy to navigate, clear/concise, modern (in terms of style and layout), functional, branded, and motivates the visitor to do business with you. Information such as hours of operation, location, and contact info should be extremely easy to find. If you have social media profiles, buttons linked to these profiles should be present. People want a quick solution to their problem or a quick answer to their question. Make it easy for them. They also want to look at something that is visually appealing. Give them that with a quality website.
A quality website looks good in all browsers. You should browser test your website to make sure it looks right and functions properly across all browsers.
A quality website also looks good and is easy to use on a mobile device. The current trend of increasing mobile use to access the internet means your website needs to be properly built and designed for optimal mobile viewing.
A quality website is also well-polished. This means it has no spelling or grammatical errors, no lame clip art, no 1995 web design traits, no blurry images, no loose ends. Your content is complete and visually appealing. Fonts match across the entire website and font color and size choices have been properly made (yes, this means no lime green size 18 font on a white backdrop with a flashing clip art graphic underneath it).
People search the internet for businesses, products, services, etc. The days of relying on phone books are long gone. If someone needs to find information, they are most likely turning to the internet to find it. When they search for something you offer or specifically for your business, you want to show up- and not just show up- but show up and look good.
Looking good is important because your website is often your first impression you give potential customers. If they found you through a search or through a link a friend gave them, your website will be your first point of contact with them. Before they even see your store or talk to your staff, they will see your website. You want that first impression to be a good one.
Your storefront and showroom look good, right? Why do they look good? Because you know customers will see them and form an opinion about the business based on them (in addition to factors such as customer service, quality, price, etc. of course). Think of your website as your digital storefront and showroom. People are looking at it and are forming an opinion about the business based on it. So make it look good!
Your website is a tool. Make that tool quality from the start. Then use it and take good care of it.