Code review request for fizz buzz
In both versions, your policy on printing newlines is inconsistent.  With fizzBuzzBetter(), all of your cases are mutually exclusive, so they should all be System.out.println(...) calls, and there is no need to prepend "\n".

Your fizzBuzzBad() is wrong: it won't print "fizzbuzz" for multiples of 15.

Anything that can easily be parameterized ought to be.  Instead of hard-coding 20, your functions should take a max parameter that is passed from main.