Is your car's warranty at risk if you skip a scheduled service?

Although they're designed to make your life easier in the long run, scheduled services can be a pain when they pop up out of nowhere and add to your living expenses. It's easy for an annual service to slip through the cracks. Before you know it, it's six months since you got that first reminder and you're encountering some kind of mechanical issue that probably could have been avoided. Where does this leave you with your car's warranty?