Music is art man. 2 minute songs, 20 minute songs. Intentionally bad production or dissonance, constant repetition or no repetition or record 60 minutes of insect noises (see Tribes of Neurot - Adapation & Survival) . Our guitarist played with his left hand upside down (so similar to a keyboard or steel guitar) allowed him to do things other people couldn't. You don't have to break the rules but it can definitely lead to innovation or something unique.
Lots of folks have different ways of learning, some are self taught, some had instructors, some know tons of music theory, and there are some great artists that don't know hardly any music theory at all. In the end if you like what you hear, then keep doing it.
Plenty of rules/practices that Dwarf Fortress doesn't abide by whether be the graphics (particularly before the steam release) or balance, and probably behind the scenes in the code but we still love it.