Because static in normal compiler, it is initialized before all the other variables and classes. so the problem is the life cycle of a singleton . in theory, it end up with the application termination.
or else it eats ur memory all the time but back to the real situation, you still need to see if this singlton has state or attributes or not. that is the root of the memory killer.
so do the calculation or benchmark your application then you will know if it is ok or not. dont forget the java is running on server-side.