A ball doesn't roll forever after being kicked in a soccer game due to several factors that work against perpetual motion:
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Friction: The primary reason the ball stops rolling is friction between the ball and the ground. This includes both sliding friction (between the ball's surface and the grass or turf) and air resistance (drag from the air pushing against the ball as it moves).
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Energy Loss: When the ball is kicked, kinetic energy is transferred to it. However, as it rolls, some of that energy is lost due to friction and deformation of the ball. This energy loss slows the ball down until it eventually stops.
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Inclines and Uneven Surfaces: If the playing surface is not perfectly flat, any inclines or uneven areas can cause the ball to slow down or change direction, contributing to its eventual stop.
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Impact: If the ball encounters obstacles (such as a player, a goalpost, or the boundary), it can change direction or come to a stop.
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Air Resistance: As the ball rolls, it pushes air out of the way, creating drag that slows it down. The faster the ball moves, the more substantial this effect becomes.
These factors combined ensure that the ball can only roll for a limited distance before coming to a stop.