Defects in the PCB manufacturing and storage process are similar to those in other electronics and are sensitive to environmental factors like temperature, humidity, and pollution.

1. Temperature: PCBs are affected by temperature during storage and installation, which can lead to component failure due to temperature fluctuations and expansion/contraction.
2. Moisture: Exposure to moisture during manufacturing and storage can cause short circuits and damage components due to corrosion.
3. Contaminants: Pollutants and dust can weaken PCB performance during manufacturing and storage.
4. Impact: Violent drops or improper manufacturing can lead to excessive vibration, damaging the PCB alignment.
   PCB soldering process defects include open-circuit solder joints, excessive soldering, component displacement, webbing and splattering, pad warping, solder balls, mechanical defects, and defects caused by electrostatic discharge.
   Methods for finding PCB defects include visual inspection, X-RAY inspection, AOI inspection, FCT inspection, and ICT inspection. Visual inspection is common and can identify manufacturing defects, while X-RAY inspection can check internal structures without damaging the PCB. AOI inspection detects dimensional defects, while FCT inspection checks functionality under real conditions, and ICT inspection checks electrical performance.