Regardless of whether your car was maintained well or poorly, it is always wise to perform an iron decontamination (along with a mechanical decontamination) as preparation for a wax, sealant, or coating. The reason for this is that if you are going to apply an LSP (last step product) such as one of these mentioned, you don’t want to be sealing in any iron contaminants, which could continue eating through your paint. If you ever plan to apply a protective wax, sealant, or coating, consider doing an iron decontamination with an iron remover.
Birds leave droppings on our cars all the time; dealing with the problem is easy. Most people would go get some water and wipe the bird dropping with whatever rag or paper towel they can find. Something so innocuous can actually cause damage to your car’s paint. If you know how to properly clean bird poo off your car’s paint, you won’t have to worry about creating scratches in your car’s paint. It doesn’t take much more effort to properly clean off bird poo, so its worth doing every time you encounter bird droppings on your car.
Using a clay bar prepares a car for further car detailing that may be needed. Whether you are doing paint correction with polishing or compounding, or maybe you just applying a wax, you will be doing it using an applicator that abrades against the surface of the vehicle. If the car wasn’t clayed prior to doing those things, then very particles will still be on the surface of the paint. Therefore, doing any sort of detailing work will effectively take those particles and scratching them all over the surface of the paint. Using a clay bar (after an exterior wash), is a critical first step towards preparing your car for additional detailing work.