2008 Prius Touring-68K, new catalytic converter needed

Hi Prius enthusiasts,

This is my first post, and I've been a longtime lurker on this helpful forum. Thanks everyone for the advice!

My '08 Prius Touring is in the shop today because the 'check engine' light came on at 68,500 miles. I just got word from them that the catalytic converter is bad and needs replacement. Good thing I bought the extended warranty! Well, I searched the forum for similar problems and it seems like this is somewhat common, albeit on cars with a bit more mileage and maybe a year or more older. I don't abuse my car at all, though I often roll into full-throttle while merging.

Is this a symptom of a poor part design or of a system that fouls the cat over a certain amount of time? I'm not looking forward to replacing it again at 130K after my extended warranty expires.

Anyhow, I just wanted to share that in case there are others with a similar problem.

Cheers!