The warranty is certainly not "it will keep the data 10 years without being powered on." We discuss the topic of how long SSDs retain the data when powered off. Intel says, powered off but stored on just 35 degrees C, only 14 weeks, as published by AnandTech:
And Intel is proud to be more reliable than others. In one of their presentations I've seen they show that they use some very high tech setups (like accelerators!) to measure the degradations fast, and that the other producers fare worse on their tests.