Ok, I run 38.5x12.50 SX tires.
Why? Honestly I can run 95% of the trails out there on 33's. I chose the tire size I did, merely because I wanted to and occasionally try legal obstacles that need the clearance.
Now days most of the time I'll put around in 2WD LO.
How did I get there though... Back in the day I bought a 92 YJ with no flex, 3.07 gears, open, and thornbirds. I learned to drive for 1.5 years. Then my jeep went through a major change and went to 36"SX tires. I found I could crawl over everything, but I also found that if I got hung up somewhere I could create gigantic holes even with well worn SX's. Sure, I might be able to power my way out, but how much damage am I doing in the process? If little/none I'll continue, if I'm starting to create a hole or make one deeper I'll try a different line or pull cable.
Today, everyone seems to just want to upgrade right away. Don't spend time learning on a stock (or less in my case LOL) like rig, just upgrade and hammer down when needed. I can't count how many times a trip I see BAD driving out there, and if I'm near it I will take the opportunity to try and educate the driver. But there's also a lot of drivers that will nod with you but go back about their business the minute they think I'm out of their sights.