In this picture the person on the right-hand side of the seesaw is heavier than the person on the left although they are both sitting the same distance from the centre of the see-saw. This obviously causes the see-saw to tip over to the right hand side.
The analogy with the forklift can be seen on the right where the load being carried is too heavy for the rated capacity of the truck. Needless to say this would cause the truck to tip over in a forward direction. The load being carried should always be within the rated capacity of the forklift. In order to establish this capacity it is imperative that the operator reads and understands the capacity plate which is found on the machine. There will be more information about capacity plates on later slides.