We recently replaced the wood siding on this 10 year old home that was improperly installed by the original builder here in Dallas. 
When installing wood siding it is imperative that all 6 sides of the wood are primed. We also believe that there needs to be a small gap behind the wood for water to run down to the ground without becoming trapped behind the wood and rotting it out from the backside. This is what happened with this house.
The builder installed 117 siding straight on top of tar paper and then came back 6 years later and patched in tyvek without doing the proper overlapping or taping the seams. The result was every time it rained the home owner had a pitcher of water on his kitchen floor, which came in from the window. Not only that, the original wrapping did not go under any of the window trim or corner vertical trim creating all sorts of damage to the exterior sheathing.
We stripped off all the siding and installed tyvek to code and taped the seams. We also removed all the window trim and installed the house wrap under the trim to create an much tighter barrier. Additionally we foamed all the windows and installed window flashing to move water around the windows during heavy rain. We used hardie trim around the windows to prevent future rot from occurring, and we also used chloroplast to give us a 1/4″ gap which allows water to easily move off the back side of the siding if it penetrates. This system is far superior to any other system in place and should prevent rot from occurring on this home.