Although there is a clear answer to what comes first, it often depends on whether you ask the developer of a product (e.g. website, mobile application or online platform) or a product designer/owner.
What is UI and UX?
For the latter – product designers/owners – the UX constitutes a user’s entire experience of using the product, particularly whether it is pleasant to use and whether it does what the user is looking for. The UI, on the other hand, constitutes the tools with which this user interacts with the product, namely the buttons and functionalities of the software product, and the device that it is installed on. Developers, however, often don’t see the UX and UI as two different things, for together they should result in an interface that is user friendly, which helps the user in performing its tasks and hence makes it a pleasing product.
Developers vs. Designers
This is a bit confusing, but the problem arises because the developers often receive the UI in the form of wireframes, and then have to code it in the best way possible in order to ensure a positive UX. However, before developers receive their UI wireframes, the product designers/owners have to imagine their user’s experience before they can design it. They do this by defining the specific personalities (age, education, skills, background, etc.) of their target group and analyzing the way that they intuitively interact with a system like their product. Subsequently, each step in this interaction is optimized in order to improve the usability of the product and hence generate a positive UX.
Comprehensive UX design leads to an intuitive UI
In order to create a good product, then, UX design must always come first, because it involves the analysis that will determine the wireframes that the UI design is built according to. Thus, the User Experience is essential to create a User Interface that is intuitive for your target group, because without defining the UX beforehand it is hard to know how your target group prefers to navigate a product like yours.
Simply put, if you want your product to be successful, you have to ensure that people like to use your product. In order to achieve this, it is crucial that you take your time to get into your users’ heads, and to not just imagine them but to define them as comprehensive as possible. Only then you can analyze their behavior properly and create an interface that matches their tendencies. Finally, always make sure to get your product built by a team that includes both product designers and developers, because only then you will get a product system that is both user friendly and efficient.