We place a lot of demands on our windows. When they're open, they're supposed to let in light and fresh air, and when they're closed, they're supposed to shut out the rain, cold, and heat. With all these demands, we also expect them to continue to work well for decades.
Wood windows have served a lot of homeowners well in covering these demands through the years, but even with low-maintenance exterior cladding, the wood tends to swell and shrink in response to temperature changes, hence, compromising its durability.