Most features in the LaTeX typesetting system have to do with line wrapping. The latex internal algorithm has to decide which position each word gets and at which situation a hyphenation is needed. In the screen left the normal LaTeX typesetting behavior is shown. The result is a justified text which has no longer whitespaces. This makes latex the better choice over alternatives lies libreoffice. But inspite all the comfort, there are three hyphenation signs available which can be reduced to zero with the microtype package. On the right side the improved version is shown which is also LaTeX but with the recent version of the mentioned package.
On the first look it looks like magic how the words were formatted. Because it is the same text with the same font but this time microtypographic modifications were made which are not visisble for the untrained eye. The only thing what can be recognized easily are the missing hyphenation. Similar the normal latex output in the left window, no whitespaces are there and the paragraph looks easy to read.
Similar to most of the LaTeX feature the end user has nothing to do but the package is working in the background. Somewhere in the lyx settings there is the option to activate the microtype package which is recommended for improving the rendering and then latex is doing everything by it's own. That means, the same created text will look improved without any human intervention.
This emphasizes the leading role which is played by the latex typesetting system. The self claim is, that the software produces higher quality than any other word processing software and is easier to use than commercial alternatives. And yes, compared to the justified text of libreoffice or the archaic left justified text of a webbrowser the rendered pdf file looks amazing good. It is comparable to the quality in a printed book.