I for one will be buying a 4 year old Volt on Ebay, but it will be me taking advantage of your perception of the battery pack reliability. If everything else on the Volt is designed to last (cross my fingers) then the powertrain will last and last and last and no one realizes this yet because they're calibrated their expectations on a machine with thousands of moving parts just in the automatic transmission. We're talking two moving parts here - the left side rotor, and the right side rotor. As for the battery pack, I'd be happy to inherit it with 40000 electric miles - that corresponds to 500 cycles on this chart (because it's 100% DOD)Of course a smart Volt Owner at the end of 4 years would sell their Volt to an unsuspecting person on Ebay, who didn't do their homework... and let the bozo buyer pay for a new lithium battery pack.
I don't need a new Volt because I live 4 minutes from work and go the entire way there without turning on my Honda Civic but having built an EV, I can't wait to recapture that SMILE on my face the first time that I drove it. And I'm going to be laughing all the way to the bank while driving my used Volt in 2016 (I'm buying the 2013 model year - trust me - that's the big thing if you want reliability - don't buy the 1st or even the 2nd model year)