Opening and closing quickly time after time in a short period of time is the only issue with a properly made spring. A AO or auto is made with a spring designed to last during normal opening conditions, but if you sit there and endlessly open the knife while watching TV, then you are heating up the spring and you may cause a failure. Think of bending the old wire hanger so you could break it into sections....bending it quickly 20 ro 30 times produced enough heat to break the hanger wire. Well made springers are tempered to help prevent this, but none are designed to be opened a 100 times in 15 minutes....