Why do your sponges not rise?

Sponges may not rise due to several factors, including insufficient leavening agents like baking powder or yeast, which are essential for creating air pockets. Additionally, if the batter is overmixed, it can develop gluten, resulting in a dense texture that hinders rising. Another possibility is that the ingredients, particularly eggs, were not at room temperature, affecting the batter's ability to aerate properly. Lastly, expired ingredients or incorrect oven temperatures can also prevent sponges from rising effectively.