Exactly this. Anyone who has worked with a junior developer understands this intuitively. They spend a week smashing their head against the desk figuring something out, then in review, you (the senior dev) can look at it for 30 seconds and see all the holes they missed and think of a simpler solution that uses 1/3 the amount of code.

Simplicity is a skill and it's hard to do. There's a reason most people are not minimalists despite the almost universal western desire to "have less stuff".