Chickenpox vaccine -- does it necessary?

A mother planned to bring his child to the children's clinic for chickenpox vaccine, as advised by the paediatrician. However, the grandmother told the mother it is better for the child to have natural chickenpox infection. The mother was confused with two different opinions and asked," what is a better option?"
I agreed with the grandmother partly as a natural chickenpox infection can confer 100% protection againt further infection. In comparison, the current chickenpox vaccine has only 95% efficacy against natural chickenpox infection. Then why the doctor still advised for chickenpox vaccine?

Firstly, the unfornated 5% vaccinated children will have very mild chickenpox infection, less than 50 spots. This is in case they are exposed and infected.

Secondly, we can reduce the risk of chickenpox ionfection that has very untimely occurence e.g. school examination, family trip or during her pregnancy.

Thirdly, the child need to miss school and the mother need to miss work if the child has chickenpox. If there is small infant, pregnant lady or elderly people at home, the isolation issue need to be addressed.

So, I opted chickenpox vaccine.