Since streaming services became popular a few years ago, subtitles have become an increasingly important part of our lives. On top of now being able to watch films and TV series for hours on end without even touching the remote control, this also caused the demand for subtitlers and subtitle translations to increase.
Given that everyone is now exposed to subtitles, even those countries that have historically preferred services like dubbing or respeaking, and that many translators without any formal training in subtitling have turned subtitlers, the quality of subtitles and the definition of errors in subtitles seem to have changed.
After a couple of colleagues asked me for some guidance on how to proceed, I thought of putting together some sort of reminder highlighting the most common errors that I have seen while QCing subtitles. Please note that all the information I've included were taken from what I have learned at the University of Leeds and from subtitling literature, mainly from what Jorge Díaz-Cintas and Aline Remael explained in their book Audiovisual Translation: Subtitling.