Why might one also use a blank constructor?

Question

I was reading some Java recently and came across something (an idiom?) new to me: in the program, classes with multiple constructors would also always include a blank constr

Answer 1

I usually write one constructor that fully initializes the object; if there are others, they all call this(...) with appropriate defaults.

An object should be 100% initialized and ready for use when it's created.

Some frameworks, for example Hibernate, demand a no-arg constructor. The way they clash with best practices makes me uneasy sometimes.