Outfit for your first day of work

This morning, when I got the bus on my way to the work, one girl came in and asked to the driver her bus stop. Today was her first day of work.

I do not know which work will be... but I would like to launch a question: Would you go with a veryyy basic brown t-shirts, jeans and flip-flop to your work?... and the most interesting issue: would you wear that outfit your first day of work?

T-shirt.... jeans.... but flip-flop??????????