Students often come to us with expectations that we will teach them how to write and speak correctly. Why correctly? Because they know it produces rewards: money, jobs, status. Although the scientific linguist says that correctness is just based on the preferences of the cultural group with the most status, and has no intrinsic merit by itself, still the popular attitude has it right: Correctness works to help you get ahead.
Similarly, poor spellers have a lid on their success (unless they are musicians or star athletes). Admittedly, there is little correlation of either correctness or spelling ability with heart, or character, or intelligence, or spiritual development. The real reason for correctness is that it works, in certain social and professional situations. It brings rewards.
It is not more moral or beautiful by itself. Correct language is just what the power elite says is correct. You need to make a choice: would you like to achieve certain financial and social goals? If so, you need the tools to get there. Above all you need a set of verbal options. Just match the tool to the situation appropriately, and you win the prize. You get the approval, or the promotion.