Without consistency derived from entering every transaction, the data is a crap shoot. Few people are capable of remembering all the relevant information about every customer and then producing easy to understand reports from that information. Software permits systematic, consistent application of rules for managing sales people and sales floors. Software makes it easy to maintain contact with buyers and non-buyers. Software permits routine evaluation of different promotions, product lines and sales people.
Software is easy to use, easy to install, and cost effective.
A package with all the functionality above costs less than a the typical store spends in one week on advertising and comes with a money back guarantee. No card file is used all the time. No sales person, no matter how smart, remembers every thing you need to know to make crucial product line and advertising decisions. Software works because the simple act of entering the UP and sales data when the sale is made provides all the benefits outlined above without additional work. Card systems might work for collecting data and may work for tracking information about one customer on a case by case basis, but they never work for producing reports on key trends across different customer groupings.