Why do people fluff their pillows before they go to sleep?

People fluff their pillows before sleeping to enhance comfort and support for their heads and necks. This process helps to redistribute the filling material, ensuring an even surface and maintaining the pillow's shape. Fluffing can also create a cooler and more inviting sleeping environment by allowing air to circulate through the pillow. Ultimately, it contributes to a better night's sleep by promoting proper alignment and relaxation.