Why do some planets have shorter length of days than Others?

The length of a planet's day is primarily determined by its rotation speed on its axis. Some planets, like Jupiter, rotate much faster than Earth, resulting in shorter days, while others, like Venus, have extremely slow rotations, leading to longer days. Factors such as a planet's size, composition, and the influence of gravitational interactions can also affect its rotational speed. Additionally, events in a planet's history, such as collisions or tidal forces, can alter its rotation over time.