That is because lip brush is easier to have quality problem. If there are powder brushes, blush brushes, foundation brushes, eye brushes, lip brushes etc in the makeup brush set, all other brushes have the same quality standard, that is: no lose bristles, no marks on ferrule and handle, the handle and ferrule should be smooth and straight etc. It is easy to check the quality, and will cost less time.
While for lip brushes, it is different, besides the above quality concerns, you should pay attention to the following possible problems:
2. If the brush head is protected with a tube; as lip brush is pointed, which may be out of shape during shipment, so lip brush head should have a protective tube.
3. If any bristles are backward by the tube. since each lip brush should have a tube covered around the bristles, it requires a lot on the techniques and is easy to have backward bristles, while backward bristles are not qualified.
4. If the lip brush is retractable, ensure the retractable mechanism works well and have enough life time for daily use.
Of course, besides the above aspects, you should also check the lip brush ferrule and handle etc.
While custom makeup brushes from the makeup brush manufacturers, customers should clearly express quality requirements on the makeup brushes in the purchase order or agreement and ensure that the makeup brush manufactures have completely understand all requirements, so that customers can get the exact brushes you need and will avoid of possible conflicts.