1. The packaging protection of LED flexible light strip is not perfect, resulting in damage to the lamp beads due to impact during transportation.

2. The solder joint of LED flexible light strip has a false solder joint. The vibration during transportation causes the solder joint to fall off, causing the light strip to not light up.

3. LED flexible light strip has less soldering tin, and solder joints are easy to fall off.

4. The soldering tin quality of LED flexible light strip is poor, and the solder joints of LED flexible light strip are easy to crack and fall off during the bending process.

5. When installing the LED flexible light strip, the bending angle is too large, which causes the LED flexible light strip solder joint to separate from the copper foil, causing it to be off.

6. During the installation of the LED flexible light strip, the product is excessively squeezed, which causes the chip of the LED flexible light strip to be damaged or the solder joint to be deformed and fall off and do not light up.

7. The solder mask layer of LED flexible light strip PCB is too thick, so the solder and PCB cannot be completely integrated during welding, which is also a phenomenon of faulty soldering.

8. The LED flexible light strip shall not be twisted during installation. If it is twisted, the solder joints of the LED flexible light strip will fall off, resulting in no light.

9. The static electricity is burnt out. Because LED is a static sensitive element, the chip will be burnt out if the static electricity protection measures are not taken.