Some 10x engineers just say "No" to product owners. If you let a product owner to convince you that you need an .xls export rather than .csv for internal use (this is a real-life example!) you may add a week+ of work/maintenance versus the time it takes me to explain "no."

> an .xls export rather than .csv for internal use

Presumably this was a trivial data dump and not something like a report that could have benefited from, e.g., embedded formulas, multiple sheets, etc.? (I've produced exports with the latter and the enhancements were greatly appreciated over the plain old CSV export.)

From my experience it's the opposite, a mediocre programmer will create way more code than needed because they don't try to understand, but just blindly copy conditions and cases they see in the surrounding code (cargo cult). This leads to more convoluted code that looks clever and covers edge cases that wouldn't exist if it was coded properly or if they pushed back. Then the experienced programmer comes in and rewrites it to solve the actual problem with as few lines as possible.