Clerks were skilled in the sense that they had to know what was the important information on those pieces of paper, and in which books such information was to be written down. ICT changed all this. Now, virtually all bank transactions are processed electronically with minimal intervention from human workers.
As a result, the bank clerk has become extinct, or at least an endangered species. Such changes occurred not only in banking but in all industries. Any task that could be programmed was moved onto electronic platforms, displacing workers in the process.