I don't mean to offend anyone, and I'm sure there are folks out there with legitimate problems that necessitate getting a new phone, but having said that...
If every EVERY smartphone you've had has to be replaced MULTIPLE times, then there may be chance you're the one with the problem.
It seems like with every device there's always folks in forums saying their on their 3rd or 4th (or 5th or 6th...) device and it still doesn't work right. I don't know if some of these folks are abusing the device or just demanding a level of perfection that is beyond absurdity, but frankly I'm surprised Verizon doesn't just "see ya!" and terminate the contract.
(Again, I KNOW there are folks out there who have REAL issues who deserve to have a lemon swapped out for a working device, I know that)
Before my Thunderbolt, I've had the following devices:
BB Storm, BB 9650, BB Storm2, Droid Eris
Every one of them, including my Thunderbolt, I had only 1 device the entire time (and those are some of the devices with the most reported problems!).
Verizon (et al) could probably save TON of money by actually training some techs to diagnose and fix problems rather than just swap devices. I guess it really bothers me though because I have to imagine that all of this is a contributor to what drives prices higher each year; higher prices for phones, higher prices for plans, lengthier contracts terms and lengthier phone upgrade eligibility periods.
Sorry for the rant.