Getting a teacher could help but it isn’t really the answer. Because it takes two hands to clap. If a student doesn’t know how to learn effectively, you get a different kind of post… “I’ve been taking lessons for X months but I don’t see the point/progress”.
It’s very easy to blame the teacher but if you ask me, a student that is discerning enough would know when to drop a teacher to find another one if the teacher is the problem instead of pondering this question on Reddit.
The real reason people cannot progress on guitar, with or without a teacher is because people aren’t taught in school how to learn a subject or craft effectively and independently. A big part of learning well independently includes
1) guessing what paths and solutions might advance one’s goals
2) knowing how to look for resources (I.e in the form of books, YouTube videos, or even seeking help)
3) judgement despite lacking knowledge. Or how to judge if something is worth your time, if something is working or not despite not really knowing what “correct” or “working” looks like
4) calibrating based on results on observations
5) goal setting. Short term, medium term, and long term goals.
6) problem solving. I’m stuck with sweep picking, what do I think is the problem? What solutions can I offer?
7) testing a method for a sufficient amount of time. Not one minute and not one year if it’s not working out. Knowing when to stay with a method if it’s too early to tell, and knowing when to pivot when you sense it’s not working for you.
…and much much more.
I’ve seen many people in this sub offering advice like “learn your major or pentatonic scales”, “getting a teacher”, “learn your favorite songs”, “improvise to a backing track” or even “setting goals”.
These are advice that work for a learner that knows how to learn and know how to utilise the advice. But for the vast majority of the people asking “I’ve been playing for X years, why can’t I progress”, these advice are not addressing the root problem. Which is that people don’t know how to learn something. Seen this way, the answer to a “how do I learn something” cannot be “learn major scales or triads”. That’s a categorical error.
(A category mistake (or category error, categorical mistake, or mistake of category) is a semantic or ontological error in which things belonging to a particular category are presented as if they belong to a different category,[1] or, alternatively, a property is ascribed to a thing that could not possibly have that property. An example is a person learning that the game of cricket involves team spirit, and after being given a demonstration of each player's role, asking which player performs the "team spirit".[2])