Risk-Based Testing prioritizes testing of features, functions, etc based on the risk they represent either on their importance or the likelihood of failure. This can be extrapolated further based on the revenue loss to the company, problems for the customer, or further if you'd like. Yesterday, I found myself applying it to buying a car.
The car in question is a 99 Porsche Boxter. She had good miles and a good price. I went to test drive it and found a few issues for negotiation. There was light, but extensive hail damage all over the car, the air conditioner was not working (not a fun test drive in 94 degree heat) and the temperature light was flashing, although the temperature dial was showing the car was not overheating. Otherwise, the car ran like new.
When I began negotiation with the dealer, they immediately offered to fix the hail damage. I took that in consideration and added that they would need to fix the air conditioning and the temp. light.
After more negotiation, we were nearing the price I wanted, but still not close enough. I knew their concern was about the cost of the potential repairs. How much would it cost them to sell me the car? Then I looked at what I wanted fixed, hail damage, Air Conditioner and temperature light.
I love watching BBC car shows, especially Top Gear and Wheeler Dealers. Wheeler Dealers buys older cars, fixes them up and sells them for a profit. One of my favorite episodes was one where they bought a Porsche 911. They would talk about problems saying, "this could be simple, or it could be expensive, Porsche expensive".
That phrase kept running through my head, "Porsche expensive".
So, instead of raising my offer, I dropped my fixes. I offered them the same dollar amount, but dropped the hail damage. I knew I could get that fixed fairly reasonably, but I had no idea about the air conditioning and temperature light. Those were high risk.
The salesman looked at me, smiled and said, "I see what you're doing, you know what the hail (damage) is, but you don't know about the rest. Smart move."
That got the price closer to what I wanted, but in the end, we left over a matter of $500. I expect I will get a call in a few days if it isn't sold.
Anyway, that is risk-based testing in action. The air conditioner could be a simple belt replacement a system recharge, or it could mean a new compressor and cost a couple of thousand dollars. The flashing temperature light could be as simple as low coolant, or it could mean a complete engine rebuild. Light hail damage can be removed via paintless dent removal, a few hundred dollars at the most.