How to judge the quality of nail polish？

Nail polish is a cosmetic used to modify and increase the beauty of nails. It can form a friction-resistant film on the surface of the nails, which can protect and beautify the nails. The quality of nail polish on the market is uneven, how do we judge the quality of nail polish?
1. Nail polish has a suitable drying speed and can harden
2.Nail polish has a viscosity that is easy to apply to the nails
3.Nail polish can form a uniform coating film 
4. The color of nail polish is uniform, whether there are floating objects in the bottle 
5. The gloss and tone of the film can be maintained for a long time
6. The adhesion of the coating film is good
7. The coating film has a certain elasticity

8. Easy to remove when scrubbing with nail polish remover