Teaching yourself is an interesting idea.
Most people who consider themselves self taught actually had a teacher, it’s just the teacher wasn’t present at the lessons but instead was in a book, dvd or website.
This is fine but it has its drawbacks, mainly, with no teacher present the student is free to practice bad habits and poor technique without being corrected.
To put this in perspective, i made more progress in one year between the age of 17 and 18 than i did in the previous 10 years. It just so happens that at 17 i was introduced to a really good guitar teacher, up until that point i had considered myself self taught.
So yes, you can ‘teach yourself’ a certain amount and you might get lucky and develop a great technique regardless but i wouldn’t bank on it.
Even when i worked in Spectrum Music (Whitefields music shop) i would tell everyone who bought a new instrument to get a couple of lessons to start off with, just to get the basics down and form a good technique.