Test This Light Switch

Feed fromtestthisblog.com

We’ve been interviewing to fill a couple QA positions on our team. My favorite part of each interview is my “test this light switch” exercise. It reveals interesting skills about each test candidate.

I point to the light switch in the room and say “test this light switch”. Here is a sampling of how candidates have responded:

• some asked if there are any requirements (this is a great way to start!)
• some just start testing with lots of assumptions (no so great)
• one candidate smiled and thought I was kidding. After asking lots of questions to prime him, he stared uncomfortably at the light switch and offered me close to nothing (embarrassing for both of us)
• one candidate walked up to the light switch and began testing it as she walked me through her thought process. After some solid high level tests, she wanted to see electrical schematics for the building and asked me all kinds of questions about emergency backup power, how many amps the room’s lights draw, and what else was on that circuit. She wanted to remove the trim plate to check the wiring for electrical code standards. She asked if the room’s lights could be controlled by a master switch somewhere else or an energy saver timer for off-hours. (these types of questions/tests make her a good fit for my team because my AUT’s weakest test area is its integration with other systems)
• one candidate was good at coming up with cosmetic and usability tests (e.g., Is the switch labeled well? Can I reach it from the doorway when the room is dark? Does the trim plate match the room’s trim in color and style?)…not so important for my AUT but good tests for others perhaps.
• one candidate went right for stress tests. He flipped the lights on/off as quickly as he could. He tried to force the switch to stay in the halfway-off-halfway-on position to see if it sparked or flickered the lights.

More was revealed about the confidence of each candidate, their creativity, how technical their brain was, how quickly their mind worked, their persistence, and finally how interested they were in determining their mission and what I thought was important to know.