Your question is a very good one. I would love to be able to write clean code from the start.
However, when we record the course, we sometimes code a single lecture in the best way to demonstrate the principles of that lecture. This is not always the best way to structure the entire program, so we eventually have to reconcile the two and do some code cleanup. Because this is fairly mechanical, and the process for tidying up the code is orthogonal to the process for solving the problem, we sometimes put the two tasks in separate lectures instead of tidying up in context.
The truth of the matter is that ALL code sucks. I've never written a perfect program on the first try my entire life, and it is a continuous iterative process. In fact, I have NEVER written a perfect program. I would go as far as to say that for some development task "Refactoring" (a fancy way of saying clean up your own messes) is the majority of the effort.
Mostly, you try to remove your own contributions and let the problem express itself in code.
We are imperfect, thus what we create is imperfect. At the risk of sounding like a buddhist monk, acceptance of one's own imperfection is the only path to betterment. For what it's worth, this is a lesson I have learnt with programming, but that I still struggle with daily as a person. What we show in the lectures is only an honest reflection of this Truth.
When you come to develop your own games, you'll find that you face similar situations to ours. Your code will suffer from many issues. Learning how to turn very ugly code into only slightly ugly code is actually a very important skill. It is also rather well remunerated.
In addition, we often notice problems with what we have created once we review the recording. We prefer to share it with you even if the video is slightly lacking, because we believe imperfect things can still have value, and it lets us move on to another topic, which gives you more value than if we had polished the original recording.
Perhaps it would not be too far off to say that our course, with its myriad problems and flaws is a reflection of the wabi aesthetics.
If you are just starting as a programmer, my recommendation is that you drink deeply from other sources of knowledge than just our course. Take other courses, read books, try new and different languages. Our collective imperfections will not overlap, and it is only by looking at many people's effort that one may see the shared platonic beauty and truth of programming below each.
It may seems strange to talk about the philosophy of programming, or of video course creation. But these activities are just reflections of craftsmanship, which in turn is just a reflection of our lives.
Right, now back to code :-)