I agree both Selina and Chanel are not well trained as well as their service and attitude are YMMV. However, some customers are happy to be their trainers because they do take advantage of that Yes, it is a service business. Simply pay the girl below average tip and not repeating next time, if you find her service doesn't meet your criteria. Anyways, I already told the boss about your feedback and concern. She will give the young girls lesson in the near future.