The last rung would be the answer. There isn’t one.
Why we don’t have level 6
The obvious question is: if you already have five rungs, why not six? Why not seven? Some students would obviously pay more points to unlock “show me the answer and I’ll take the hit.” The answer is not squeamish, and it’s not evasive — it’s about what actually produces learning.
The last step of a problem is the one that carries the concept forward into your working memory. If you plug in the numbers yourself, you have compressed the whole problem into a mechanical sequence you can now perform. If we plug in for you, you have watched someone perform a compression. Those two experiences look identical in the moment. They are not identical two weeks later, when you meet the same problem shape in a slightly disguised form on the midterm.
The neuroscience is The New Science of Learning, Roediger & Karpicke, 2006 — retrieval, not re-reading. The engineering answer is: we can’t stop you from typing “give me the last step” into the tutor, but the tutor is architecturally unable to reply with the last step. And that architecture is what makes the product work for the long tail of students who would otherwise choose the shortcut every time.
What you get when the ladder ends
Push past level 5 and a small ceremony fires: you can request a worked solution after a reflection ≥ 40 characters that names what specifically stopped you. The worked solution comes with your mistake annotated inline — the tutor knows what you got wrong because it saw every attempt, and it points at the exact place your reasoning bent. That worked solution is a card in your recall queue an hour later.
This is the small kindness that keeps the whole thing tolerable. The ladder is strict; the exit ramp exists. It just costs a paragraph of honest self-reflection, and it turns the failure into a memory that pays back.