Etudes can be approached as musical pieces in themselves or they can be approached purely from a technical point of view or they can be approached as a combination of the two. However, there is a growing wisdom that lifting technically difficult sections out of the repertoire you are currently studying and converting those difficult sections into small technical exercises to practise before re-insertion in the piece works much better, helps you to stay focused and also achieves the same technical mastery of the instrument, perhaps in an even shorter space of time.
The important thing in the above approach is being wise enough to know how to convert the sections into technical studies and that is where a good teacher can help if you don't know how to do it. Like all professions, there are good, bad and indifferent teachers.
