indicates. Kevin simply did not get what he was expecting out of the button. To some, it is counter-intuitive to insert the content, select it and then click on the button. Many users would expect an opening marker and a closing marker with the cursor set in between, waiting for their input. In that sense, I guess it does require some form of training.
@Cecile sorry to disagree, the user did not use the quote tool. The text "indent preformatted text by 4 spaces" gets inserted automatically when you are at the beginning of a line, have no selection and click on the code button.
If you have something on the same line your cursor is on then it inserts "Preformatted text" where that is selected for you to replace the text.
So the user did the first, but left the text there and proceeded to insert his own text below, explaining why that text was not formatted.
Yes, if you replace the text it inserts, it will always work. People who see the inserted text as a opening/closing marker won't replace it, they will write under it. That why I say its behavior is not universally understood.