Interaction Observations: CVS Self-Checkout

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The self-checkout counter has been become very popular for handling transactions. They make perfect sense as an extension of vending machines, ATM’s, and ticketing machines.

One format in particular has become popular at supermarkets and convenience stores. I observed several purchases using such a machine at a local CVS.

The Machine

The self-checkout counter has a combines several technologies that the user interacts with. The two main groups are:

  1. POS system which includes
    • scanner
    • touch screen POS interface
    • bagging area / scale
  2. Credit card terminal


Generally, the sales I watched went smoothly, but there must be frequent issues because it seemed that one CVS employee was tasked with watching over the self-checkout area.


The main issues seem to arise with payment. The credit card terminal and the POS system seem only very loosely linked. The transaction being handed off between the two seems to lead to the most user confusion. I don’t know what prevents retailers from having a totally integrated system, as the NYC MTA does for ticketing.

The credit card terminal also seemed to confuse users as to whether they could swipe, tap to pay, or insert their card. I observed a few users trying multiple approaches.

Scanning and Bagging

The pieces of the POS machine controlled by CSV seemed to work rather well. All the users I observed understood that the system worked by weighing items in the bagging area. This understanding of the system helped users debug any error messages.