Detect existing user first login flow

Getting advice
1

Hi everyone! It seems that I have a stupid question, but, I want to be one hundred percent sure that I fully understand how Keycloak works. So, there are two last sentences in the docs that say “With this configuration, Keycloak is unable to determine which internal account corresponds to the external identity”. But, everything works fine - accounts are linked properly. This statement confuses me completely. What does this statement mean? I did everything according to the section “Detect existing user first login flow” and it works fine… Thanks in advance!