Movement can be seen in the timber roofing frames of even more recent homes, rafters can become dislodged from beams and purlins due to settlement. Most vendors are unaware of issues unless shown.
Finding these problems requires a thorough inspection of the roof space, and it is preferable to be aware of them before purchasing the home so that suitable repairs can be made.
Ignoring these roof structure repairs can cause serious issues like leaks, the growth of mold, and in the worst situations, roof collapse.
As a building inspector, my role is to support the sale, not to oppose it. Frequently, the vendor is unaware of the flaws and will fix them as soon as they are found because they want the sale to proceed.