A more thorough explanation:

A derogation clause is a provision in a treaty that allows a country to not follow certain parts of the treaty. This means that a country can choose to suspend or ignore some of its obligations under the treaty in certain situations.

For example, a country may have a derogation clause in a treaty that allows it to suspend some or all of its obligations during a war or other national emergency. This means that the country can focus on dealing with the emergency without worrying about following all the rules of the treaty.

If a treaty does not have a derogation clause, then the general principles that govern the suspension or termination of treaties apply. This means that a country cannot simply choose to ignore its obligations under the treaty without consequences.

Overall, a derogation clause is an important part of many treaties because it allows countries to balance their obligations under the treaty with their need to respond to emergencies or other situations that may arise.