Ladies First

In the office building I work in, there is this policy that every tenant must have a card to be allowed access and egress to/from the building. So whenever it's after working hours, where everyone was rushing home, the card reading machine would be crowded with anxious people wanting to go home. So there is this one instance where I was walking in parallel with an anonymous lady. Stepping in front of the card reading machine together, I quickly step aside, and allow her to go first. I said "You first" in response, and watch her go before I follow behind. I had this question in my mind right after, "Why didn't I said 'Ladies first' instead?". Turning my head back as I walk out of the building, I saw a whole line of female staffs waiting to get out, so I chuckled to myself.

Seems that my sub-conscious mind told me to say "You first" instead of "Ladies first", because if I did, I would have to let the rest of the ladies behind me use the card reading machine first. I love the way my mind thinks. Kudos to layman's wisdom!