"In group settings, swings are considered to be unsafe for preschool children."
Swings are only considered appropriate for this age range (pre-school children, 2-5 years) when they are a full bucket seat. This may prevent from other kids to push the swing and cause the kid that's swinging to fall and get injured. These considerations are mostly important when in group settings, but if closely supervised by an adult, a child in this age range may swing on other swings.
