User-centered web design or web solutions is a web design principle which stipulates that the experience of the end user (i.e. the person viewing the website) should dictate how the website is constructed. Put simply, it is the experience of the user which should come first when making design decisions, rather than visual or aesthetic concerns.
It is common, for example, for a website designer (and often his/her clients) to try to achieve visually compelling web solutions using sliders, slideshows, carousels and other animated effects. However, the additional code required for these elements can bloat your website and really slow it down (which in turn can affect SEO and page rankings, as well as contributing to a less-than-optimal user experience). So unless you’re using the slider/carousel/slideshow to display your own products, you need to ask yourself “is it really worth it”? In addition, they may be taking up a lot of space on your homepage, pushing your valuable content to the bottom. The most successful web solutions will be those that use these options sparingly.
It is also important that your website is responsive, i.e. that it is built on a responsive grid framework. Most people would agree that trying to use a non-responsive website on a mobile device such as a smartphone is frustrating at best, and equates to a poor user experience overall.
Finally, the navigation of your site should be clear, intuitive and as simple as possible.