Drawback of using static member globally inside the class in c#

Static class does not allow user to create instances of the class as well as it restrict the user to inherit any data members/functions to derived class. So, imagine a situation where we dont want a user to create instance of class or dont want user to inherit it to child class. Use a static class to contain methods that are not associated with a particular object. For example, it is a common requirement to create a set of methods that do not act on instance data and are not associated to a specific object in your code. You could use a static class to hold those methods.