Reasons for the Seasons
Seasons are caused by the Earth on its axis. It takes Earth 24 hours to fully spin around once on its axis. Earths revolution takes 24 hours. Earths revolution is when the Earth goes around the Sun one time. The two reasons we have Seasons on Earth is because of Tilt and revolution.
Theres only one hemisphere at a time that can point towards the Sun. The one its pointing towards gets Sun. On Earth around the area of the equator they do not have seasons. In the winter our days are shorter and days in the summer are longer. The solstices happens around June 20-21.
If Earth did not have a axis or was not tilted on its axis then we wouldnt have any seasons or we would have fewer seasons. i dont think there are any natural occuring events to be able to change how the seasons work. If the earth was closer to the sun it woould be colder.