Differences between static class and instance class with private constructor
<p>Although a static class has only one instance and can't be instantiated, a class with a private constructor can't be instantiated (as the constructor can't be seen), so every time you call this class, this is the same one instance?</p>

<p>Factory classes always follow the last convention (instance class with private constructor). Why is this?</p>

<p>Thanks</p>
