Simply a Better Warranty
Typical fiber cement siding warranties run for 50-years, but they don't cover labor costs for warranty repairs at all. Labor coverage is critical because those costs are generally higher than the replacement material cost. Fiber cement warranties typically begin reducing or "pro-rating" their coverage after the first year. The LP® SmartSide® Warranty doesn't start to prorate until after its 5th year.
In addition, the LP SmartSide 5/50 Year Limited Warranty is transferable once during the warranty term.