Working in a team of 5, I studied people's interactions with common credit card terminals (as seen below) through a series of interviews in order to make a low-fi redesign that was more user-friendly. Check it out!
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We had our interviewees perform 15 different tasks in total. Those tasks include paying by chip, swipe, and tap on the 5 card terminals shown in below. We did not have the actual terminals with us, so to overcome this limitation, we put images of each card terminal on large screens and had interviewees interact with it by physically putting their cards up to and against the screen, and orient and perform the action as if they were actually about to pay using the specified method. We used the master-apprentice model and asked interviewees to do a talk-along of their process so we could observe and understand every step. After each interviewee demonstrated how they would pay using chip, swipe, and tap on a terminal, follow-up questions were asked in order to make sure we could capture anything part of their process we might have missed during the narrated demonstration and write it down.
Card Terminals #1-#5 (below)
Card Terminal #1: The Clover Card Terminal
Card Terminal #2: The Equinox Card Terminal
Card Terminal #3: Square Register
Card Terminal #4: Verifone Card Terminal
Card Terminal #5: Small Ingenico Card Terminal
When going through interview data for the task portions of the interviews, we were able to dissect the interviewees' actions into 4 classifications regarding how they “paid” with chip, swipe, and tap on the 5 card terminals we presented to them. These four classifications included correct actions (indicating they properly paid with chip/swipe/tap), incorrect actions (indicating they improperly paid with chip/swipe/tap), corrected actions (indicating the interviewee had an incorrect action before but changed it to be correct), and muddled actions (indicating the interviewee had a correct action but changed it to be incorrect). All of those actions except for the correct actions were considered to be a type of error. Since we had 17 interviewees and they each showed us how they would pay with chip, swipe, and tap, on 5 machines, we had 15 actions per interviewee for a total of 255 actions. Out of those 255 actions, there were 53 errors.
Table breakdown of correct, incorrect, corrected, and muddled actions (below)
Classification of errors with chip, tap, and swipe on the 5 card terminals we interviewed people with (below)
Trend: Machine Popularity
Based on our data, we noticed that out of the five devices, Card Terminal #4 was seen the most frequently, and thus it is highly likely that it will be the most familiar to most people as well. The graphical representation below shows that Card Terminal #4 beat all other devices presented in terms of frequency averaging 4.059 out of 5, and tied for first in terms of ease of use with Card Terminal #1 at 4.118 out of 5, supporting our observations of its commonality among different locations. 4 of our participants also specifically mentioned that they usually see the Verifone card reader (Card Terminal #4) at grocery stores, adding to their familiarity with them. Because of this fact, it may have the potential to influence the participants’ actions on other devices, which creates a sort of cultural standard for subsequent card readers that they may encounter. Additionally, we also discussed the idea that standardization of a product can undoubtedly strengthen the mental model that users have, and based on a designer’s perspective, would benefit from having a simplification of a somewhat nuanced action (such as swiping a card in exactly the correct orientation). As such, we took this aspect into account and weighted consistency as a large part of our redesign.
Statistics of our numerical data of ratings for how frequent a card reader is seen and how easy it is to operate for the average user in our interviews (below)
Tradeoff: Newer Conventions vs. Ease of Use
We previously identified Card Terminal #4 as the most frequently seen terminal out of the 5 terminals. Both #4 and #5 make use of older and more prolific conventions that people have gotten used to (including some of our interviewees). For example, having the chip slot at the bottom and the swipe slot on the right has been a standard convention for most card readers. Card Terminals #1 - #3 do not follow this convention however; they follow different conventions by placing their swipe slots on the top and the face of the terminal itself. We noticed that our interviewees had some trouble with these newer conventions, especially regarding swiping. The majority of all swiping errors (24 out of the 34 total swiping errors) occurred with terminals #2 and #3 alone. These machines went against the cultural constancy and convention of the arrangement of the terminal and it made them more confusing and thus harder to use. This allowed us to identify the use of new conventions as a tradeoff for general ease of use for these terminals, which of course could change over time but not without requiring people to learn how to use those machines.
Design Space:
Aesthetic vs. Signifier Clarity Design Space (below). Note: #'s 1-5 reference the card terminals above and the star represents our ideal design.
In this design space, our team has chosen the trade-off between clarity and aesthetic. We have particularly asked the interviewee’s personal opinions on each card reader prototype we choose. We have rated the scores of each prototype’s aesthetic level by collecting direct positive/negative opinions from the interviewees, like how they like or dislike the outlook of the machine. For example, 6 of our interviewees have expressed a favorable attitude towards the outlook of the first card reader prototype, “It’s white and clean, thus giving me a good impression”, “I like the white sides and the big screen of this card reader”, we have compared these opinions with the comments we received about other prototypes and give out a score of 9 (10 means the perfect aesthetic) to the first machine. To give out scores on the clarity levels of each prototype, we have estimated the times of errors people have made when they operate their card on these machines. More errors made lead to lower scores of clarity. Also, we have to consider people’s opinions/comments that directly refer to the signs on these card readers.
Lo-fi Redesign:
To better balance the trade-offs that were covered in the design space, our team has considered the following ways to enhance the redesign of the card terminals. First, since we acknowledged that our interviewees had a familiarity with certain terminals and their standards (i.e. card terminal 4), we drew upon some culturally standardized features of cards to better signify, through familiarity, to users what the correct way to insert, swipe, or tap their card is. By doing so, users will be given a familiar design to operate with and more naturally operate the new product. In other words, we are trying to create our redesign with a natural mapping based on people’s cultural understanding of the card reader. The more commonly seen and used card terminal will be more familiar to the users. By setting up the redesign similar to aspects of those card readers with commonly seen features, we can better set up the system image of operation. Also, while we have decided to use a bigger and wider touch screen and silver-colored outlook to enhance the aesthetic level of the machine, we have considered adding extended panels with signifiers to enhance the discoverability and clarity of the card terminal.
