It does not reveal how anyone voted
Custody is tracked at the envelope level. The link between voter and ballot is severed at extraction, by design. Ballot secrecy is preserved — and the engine refuses, structurally, to accept a record carrying a selection. Try to make it accept one.
It does not verify a ballot was counted correctly
Tabulation is a separate system, audited separately — typically by a risk-limiting audit. Custody evidence says a specific envelope was handled as recorded. It says nothing about the count.
It does not establish a ballot was legitimately cast
Voter eligibility and signature verification are separate processes with separate controls. A verified custody chain around an ineligible ballot is a verified custody chain around an ineligible ballot.
It does not prevent tampering
It makes tampering detectable. Nothing in this category is tamper-proof, and any vendor using that word should be asked what they mean by it. Including this one.
Why this page exists
A voter who is told that verification means more than it does, and later learns otherwise, becomes a permanent adversary. That is not a communications risk to be managed — it is the correct response to having been misled, and it is unrecoverable.
The proof is the answer. Stop explaining and hand them the verification tool.
“Here is how you check it yourself” ends conversations that “trust me” cannot. A challenger who verifies and finds the record correct becomes the strongest advocate available — so the interaction has to be designed so they can.