Why can't two methods be declared with the same signature even though their return types are different? [duplicate]

Answer 1

Because the return type isn't all that important when calling a method. It would lead to ambiguity in many cases to have methods only differing by return type. You might not store the result in a variable at all, or do something like this:

System.out.Println(myClass.MyMethod());

The compiler would have no way to figure out, which of the methods you wanted to call.