Why is there always a circle around the edges when applying nail polish/the nail polish is thick and bulging?

This is usually because the nail polish is too thick when applied, especially the edge seal is applied too much
1. Too much edge seal
The edge coating is too thick, resulting in accumulation and bulging.
2. Improper brush head control
The brush head stays on the edge for too long or the brush is too strong, which easily accumulates nail polish.
3. Too thick coating
Each layer is applied too thick, the nail polish cannot dry evenly, and bubbling or undulation occurs.
4. The nail polish is not evenly spread
The nail polish is not evenly spread in time when applied, resulting in local accumulation.
5. The bottom layer is not completely dry
The bottom layer of nail polish is not completely dry before a new layer is added, resulting in bulging and unevenness.