> Properly motivating most design patterns requires context of a sufficiently complex codebase

As someone that's made a best selling technical course, I strongly disagree.

It's 100% laziness and/or disregard for the reader.

The reason examples are as bad as they are is that people rush to get something published rather than put themselves in the audience's position and make sure it's concise and makes sense.

It's not like webpage space is expensive. There's plenty of room to walk through a good example, it just requires a little effort.