Countless people have worked long and hard to make sure that their pride and joy will look beautiful, perfect and stand out from the crowd, only to find that the final, most rewarding stage goes horribly wrong. Silicone is one of the biggest culprits and, if present, will ensure that any paint finish is in some way spoiled. Silicone is used in some polishes and cleaning sprays. And the worst thing about it is that the the presence of silicone doesn't show up until the very end of the job.
This common problem usually results in the paint layer not adhering to the substrate peeling away when dry, or as small holes appearing in the undercoat layer. It is not easy to tell whether silicone is present on your repair area so the only way to ensure you aren't affected by it is to clean.
Best practice is to use a Silicone Remover (also known as Degreaser or Panel Wipe) to remove all silicone, grease, road grime, detergents and other contaminants at the very beginning of the job and betrween each process, i.e. before and after priming, etc. in case silicone has been transferred in some way. This will ensure that the car and you will remain silicone-free during the whole repair and to help you achieve the finish you desire.