Unforeseen problems are unexpected issues that arise during a project or task. They can be caused by a variety of factors, such as changes in the environment, human error, or unforeseen circumstances. The term 'SNAGS' is often used to refer to these types of problems, as they can cause delays and other difficulties. Unforeseen problems can be difficult to anticipate and manage, but having a plan in place to address them can help to minimize their impact.