[XorNot]

For your consideration I direct you to the struggles of developing Starcraft: https://www.codeofhonor.com/blog/tough-times-on-the-road-to-...

Whereupon a huge proportion of early bugs were programmers who believed they were easily smart enough to write doubly linked list handling methods proceeded to ongoingly and continually screw up writing doubly linked list handling methods while refusing to use standard functions.

This isn't hypothetical.

[lordlic]

There is no "standard library function" for inverting a binary tree. That's not a thing that exists, probably anywhere in any standard library for any language, and even if it did you should still know how to write it yourself.

Also the article you linked doesn't argue that you shouldn't know how to write a linked list, it argues that you should implement ADT operations in functions instead of trying to wing it with ad-hoc logic all over the place. Blizzard's developers were definitely smart enough implement a doubly-linked list one time, they were just fallible humans who got tripped up consistently implementing the same logic in a hundred different places.