Why is variation Beneficial to the species but not necessarily for the individual ? Class 10

Variations are the basis of evolution.
It helps the organism adapt to harsh or new environmental conditions or changes for survival.
For example: climate change can force a species to shift its range to poleward or to higher altitude.
Only those who adapt to the changes will make it to the survival list.
If variations occur in individuals then it will be difficult for individuals then it will be difficult for the individual to survive in normal conditions.