I usually upgrade every 2-3 generations. I’ve only had 4 iPhones: 5 –> 6s plus –> 8 plus –> 12 Pro Max. I hold on to phones until the usability runs down.
Do you upgrade yearly or do you hold on to your phone as long as possible?
Edit: I honestly thought most people upgraded every year, but after reading the responses I see many people use their phones at least two years or more!