I cannot recommend Uncle Bob enough. He is most recognised for developing many software design principles and for being a founder of the influential Agile Manifesto.
Here's a bunch of free content available on YouTube. They highlight the importance of NOT creating a mess to code and the impact it can have.
- FULL EPISODE // Clean Code with Uncle Bob Episode 1 (This one is amazing!)
- Clean Code - Uncle Bob / Lesson 1
- Clean Code - Uncle Bob / Lesson 2
- Clean Code - Uncle Bob / Lesson 3
- Clean Code - Uncle Bob / Lesson 4
- Clean Code - Uncle Bob / Lesson 5
- Clean Code - Uncle Bob / Lesson 6
Check out the youtube channel: Clean Coders.
Additionally, all content can be found on their website (cost involved): Clean Coders : Level up your code.