Comment by amonks

I'm not Simon, but I think reviewing code is both faster than writing code and more difficult than writing code.

Lots of difficult things don't take very much time: shooting a bullseye, lifting something heavy, winning a round of geoguessr, playing the guitar solo from Peg. We don't call these things difficult because they take a lot of time in the moment, but because they take a lot of time to master.

I think reading code is like that too. When I think about the best code readers/reviewers I've worked with, they are (1) also among the best and fastest code writers I know, and (2) still much faster at reviewing code than they are at writing it.