A good UX is essential for any product, as it determines how easy and enjoyable it is to use. A poor UX can make a product frustrating and difficult to use, even if the UI is well-designed. Conversely, a good UI can make a product more enjoyable to use, even if the UX is not perfect.
Ideally, both UX and UI should be given equal importance to create a product that is both easy and enjoyable to use. However, in practice, it is often difficult to achieve this balance.