Why is it important to understand learning theories?

Theory goes hand in hand with practice. While it is quite easy to get results from uncontrolled practical experiments. Theory will be able to determine what contexts are necessary for predictable results. For example, getting a guitar for your birthday and messing around with it for a few days, you may be able to spit out a few melodies, but if you have Music Theory you can apply it to your accidental discoveries and create a coherent musical piece.