Okay, you walk into a public restroom and you see three stalls. Which do you choose to use? The 1st (i.e. the one closest to you?), the middle, or the third (i.e. the furthest away from you and usually a handicap stall)?
Studies have been done to see which stalls are used most often, and thereby figuring out which stalls are dirtiest and which are cleanest.
We all have our different reasons for why we pick the stalls we do. Most of us skip the first stall cause we think everyone uses that one and so it has to be the dirtiest in the bathroom. However, that changed after a study was done and showed that the first stall is the cleanest because everyone avoids it thinking it is the most frequently used.
Many use the middle stall because they want to save their brainpower for more important decisions. They don't want to take the time psychoanalyzing whether to use the first or the last and therefore just fall in between.
Then you have people that will only use the furthest and last stall even if they have to wait in line. Some do this because they get the most privacy and they don't have to worry about people peeking in the awkward cracks.
We won't even get into what would happen if someone was already in the middle stall. That adds a whole new dimension. Therefore, let us address this question with an empty public restroom.
So, for whatever your conscious or subconscious reasons, your choice is really telling us a little bit about you.