"Web browsers render justified text very poorly. They don’t have the necessary algorithms to properly set the spacing between words and even individual letters (which is what proper text editors do). That’s why justified texts come with patches of space between the words: rivers of white between the black of text. This makes it very hard to read so justifying text on the web should be avoided at all costs. Web browsers are getting better in supporting hyphenation, though. If you do use justified text, complement it with hyphenation. For now, I recommend not using justified alignment at all."

It's not like a good algorithm hasn't been around since the '70s.