I was recently hunting for an old answer of mine, and remembered it as being relatively high-scoring. To find it, I went to my answer list on my profile page, and sorted it by score. My answers were sorted by score, but the order in which answers of the same score appeared in the list seemed to be random.
This wasn't a problem, until I noticed that, when I changed from page 1 to page 2 of my answers, the page would re-roll the order of these questions! I would see, on the next page, answers that I had seen on the previous page. This means that I'm not seeing the complete list! Some answers were moving from page 1 to page 2 and back again, so that I wasn't seeing them.
I tested this with the questions page of two other users (to make sure it wasn't just my profile, and that it wasn't just the answers page). On one, I couldn't replicate the behaviour, but on the other, I could. I have no idea why.
I don't think this should be expected behaviour.