Originally Posted by whyvee

With n = 3, a randomly chosen TA has a 1 in three chance of being the right one - 33%. If we skip the first, and find that second is better than the first, then the probability goes up to 50% - now it's TA #2 vs. TA #3. Skipping TA #2 in hopes of three being better only give you a 33% chance of #3 being the right choice. It's the Secretary Problem - https://en.wikipedia.org/wiki/Secretary_problem

Also kind of like the Monty Hall problem - https://www.youtube.com/watch?v=mhlc7peGlGg