Babies may cry a lot and be difficult to soothe for several reasons. Common causes include hunger, tiredness, and discomfort, such as from a wet diaper, temperature changes, or tight clothing. Digestive issues like gas, colic, or acid reflux can also lead to prolonged crying. Additionally, babies might cry due to overstimulation, a need for physical closeness, or because they are sick or experiencing pain. Understanding the underlying cause is key to providing effective comfort and care.