Quotations in tickets currently do not show by whom they were originally made.
For example, looking at https://secure.phabricator.com/T2992#13 quotes #11 so I had to use my browser's search to quickly find who wrote that quote and when.
I would have expected something like "In reply to Joe Smith" or "Joe Smith wrote:" displayed, or at least some mouseover popup providing that info if the author info is considered too distracting for reading.