• Use of waxes or sealant and adhesives containing silicones
• Poor cleaning/degreasing
• Solvent, evaporation leaving contamination on the surface
• Use of contaminated air
• Airborne contamination
• Contamination from skin contact (Lanolin) after cleaning
• Dwell time exceeded prior to painting
• Not degreasing before sanding
  

Prevention

• Solvent clean with silicone removing compounds
• Use wipe-on-wipe-off method
• Use sufficient ventilation

Remedies

• Strip and clean or sand down and repaint