Because even the most beautiful house will crumble if it’s built on quicksand.
There’s this guy on YouTube who does drawing tutorials. Now I’m not an artist, I don’t draw with any kind of frequency. Most people would observe me to not be drawing at all! But I still watch his videos, occasionally, because he has a pleasant voice, draws good art, and makes some interesting points. Actually, that last bit is what he’s been doing in most all his videos lately. They’ve all been diatribes on the importance of fundamentals.
What he described very much applies to drawing, of course. If you can’t form a readable silhouette, if you can’t sketch up a decent wireframe, if you can’t draw a straight line to save your life, then of course the things you’ll be building on top of that work — all the fancy coloring and details that are so fun to work on — will just end up kind of… off. Bad fundamentals don’t scale, the mistakes you make early on, in the most core of processes, will be with you for the rest of the journey.
I see it in programming, too. The subject matter is very different, which means the fundamentals are very different, but the effect is still there. I’d categorize most of it under having healthy workflow, actually. Not just on the macro level, using the right tools right, but also on the micro level, constantly making those tiny improvements on the fly. Keeping your code cleanly formatted is something a surprising amount of newcomers struggle with. It’s a problem fixed by either “hard” work or knowing your tools, but it’s of utmost importance it does get fixed. Messy code doesn’t scale for the same reason quickly-written, jumbled notes can be indecipherable — its usability declines rapidly over time.
So get your fundamentals right, whatever work you do, or risk having to tear it all down to fix its foundation.