Passage: "Before the national ID, many citizens carried several documents to prove who they were, and each agency kept its own records. The Philippine Identification System (PhilSys) gives every registered person one permanent number and a single proof of identity. For people without bank accounts, this matters most: a valid ID is often the first requirement for opening one. Officials stress, however, that the system works only if records are accurate, so registrants should check their printed details and report errors at once." According to the passage, why does the national ID matter most for people without bank accounts?