Seems this "It’s because writing something new is cognitively less demanding than starting from scratch" could do with some editing. Doesn't new and scratch mean the same thing in this context?

"The reason that [ developers ] think the old code is a mess is because of a cardinal, fundamental law of programming: It’s harder to read code than to write it." Joel

I couldn't agree less with this. Currently working on a large codebase built on top of Apache ofbiz with Java. At intervals every dev involved in this project reminds our boss he shouldn't be using this codebase. Of course, events always remind us we are wrong because many features that would've taken months of dev time and work are already implemented and taken advantage of.

Anyway, takeaway, remind yourself - yeah - that reading code is hard!