The difference is, in the job interview you’re writing it from scratch yourself. On the job you have to take over from the guy who left 10 years ago and that button was designed in such a way that resizing it will add garbage data to all tables in the database and also send an email to all your customers telling them to switch providers.

A more honest code test:

interviewer: “see if you can get this project my nephew made in high school to run”

job: getting the next project their nephew made in high school to run