I like learning on my own and I got used to it :)

I need desperately a teacher or a tutor.
It would be cheaper find a language partner but definitely I have no patience with people :/

I prefer to have a teacher, because it's easier to stay motivated if I have someone teaching me.  It's also better for me to have someone else deciding when I learn what, because I have a bad habit of trying to learn everything all at once and then getting overwhelmed.  (Oops.)  And of course, sometimes textbooks don't explain things well, and teachers can clarify.

It depends on the level, the language and the experience in learning languages.

Learning materials are crucial. If the self-learners can't find suitable material, they can't succeed.

In some languages there is a great variety of good and modern material, in others ot so much.

In my case, it depends on the language. I can easily learn German, French, Italian by my own but for Russian, I need several teachers! Hehe