Psychology could be part of it, but even the focused player runs into this. I have the same problem in my survival attempts. I think a bigger part of it is that the puzzles get consistently tougher as you get more correct: it makes sense that you may get several in a row wrong - that means that is about where your puzzle ability is balancing out for the session.
I have noticed that when I do puzzle rush survival, I tend to get puzzles wrong in a row. For example, today I was doing puzzle rush survival and safely reached 27 without an error. I got 3 wrong in a row after that, it's not like they were way too tough for my level, and I have solved problems like that before. I think it's more of a psychological problem which imo every chess player faces.