Toasters typically have a wide range of settings to accommodate individual preferences for how well-done they like their toast. The reason for having settings that can burn the toast is to provide users with the flexibility to choose their desired level of toasting.
People have different tastes and preferences when it comes to toast. Some may prefer their toast lightly browned and barely toasted, while others may enjoy it crispy and well-done. By offering a range of toasting settings, toaster manufacturers cater to a broader audience, allowing each person to customize their toast according to their liking.
Additionally, the versatility of toaster settings allows users to toast various types of bread and pastries that may require different toasting durations. For instance, thicker bread or frozen pastries might require a higher setting to ensure the center gets adequately toasted without leaving the outside undercooked.
While the highest setting might produce extremely well-done or even burnt toast, it serves a purpose for those who prefer their toast that way. So, even though it might seem excessive to some, having such settings caters to the diverse tastes and preferences of consumers.