I see most posters' points.
Me - years as a lab worker, usually supervisor, in the manner of head person you can ask a question, not in the managerial sense. My first lab, I was the only person, including being the person to move the refrigerator (I was always interested in space planning, didn't know it then.) I refused the primo managerial role in a later company I worked for a few years that became rather large. I preferred the research/lab aspects, we're all different. Actually, I left because that all got claustrophobic and I was then into art studies after work.
We all wore lab coats some lot of the time, including docs.
In that last place, the Office Manager finally had a talk with a fellow not that long from a pacific island about the matter of body odor. I sort of liked him, since I've a very reduced sense of smell.
I got interested via art in landscape design, and signed up for what turned out to be four years of courses and a couple of years of internship, and what was then national boards. I passed. I'll never regret this, my view of the world expanded in bursts. Never great for the wallet, but wonderful in what I learned, expanding interests, vision, and so on. Also, some of those views changing, but that was now part of the fun.
A regret - geology, I should have gone there back in college.
But, work mode - we wore what we needed to. One place where I interned, a famous name at the time female designer wore high heeled boots to job sites - but I know those were not muddathons. She dressed for success, then meetings. I think of her as a mentor, short time, but even back then I had long ago stopped with those heels, I need balance.
In later years, wherever I worked past thirteen days (another story) was casual.
Shoes mattered. Mud happens.
Later, in business with my last business partner who was also a contractor, we both wore clean jeans and shoes that could deal with a given property.
Oh, and we did wear dresses - but usually that was not smart for walking a site.