This is more about user preference than a hard rule. In general, studies and common behavior suggest that most people prefer lighter backgrounds, especially because dark backgrounds with light text can strain the eyes more during long reading sessions. So for many websites, light mode remains the more natural default.
That said, dark mode has become more common in apps and digital products, and some people do prefer it, especially in low-light situations or at night. Because of that, dark mode can still be a useful option.
The best recommendation is to give users the choice if the business wants to include both. Rather than locking everyone into one mode, it can be beneficial to offer a toggle between light mode and dark mode. That makes the website more flexible and gives visitors control over what is more comfortable for them.
So the answer is not that one mode is always right and the other is always wrong. The better approach is to understand that people have different preferences and, when possible, design with that flexibility in mind.
The answer treats dark mode versus light mode as a preference-based design decision rather than a strict requirement. While lighter backgrounds are generally easier on the eyes and more commonly preferred, dark mode still has value for some users, especially in nighttime or low-light use cases. The speaker recommends flexibility wherever possible, suggesting that a website should ideally allow users to choose between the two rather than forcing one universal setting. The overall point is that mode selection should be guided by user comfort and brand fit rather than trend-following alone. If implemented thoughtfully, an optional toggle can enhance the user experience without compromising the site’s professionalism.