Why do my oatmeal cookies not rise spread out?

Oatmeal cookies may not rise and spread out due to several factors, such as using too much sugar or fat, which can lead to excessive spreading. Additionally, if the baking soda or baking powder isn't fresh or properly measured, it can affect leavening. Insufficient chilling time for the dough before baking can also cause cookies to spread more, as the fat melts too quickly. Lastly, not using enough flour can result in a dough that lacks structure, leading to flat cookies.