system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: How do house builders avoid weather damage while the buildings are under construction?

Whenever I see unfinished houses in a downpour all I can think about is all the places water is seeping in to cause damage. How does the potential damage get mitigated by the time a roof and siding gets added? Does the wood really just dry out enough in the sun that it is not an issue?
gpt
Depends on what phase of construction they are in.  In new construction, there is rarely any need to keep things dry during the framing phase.  By the time you need to have things kept dry you'll generally see a house-wrap and windows installed as well as a roof (either the final roof, or an underlayment that will stay there for the long run, but is temporarily serving as a water barrier.  

The crudest rule is that if you're gonna put up insulation and sheetrock the house should be dry and be able to stay dry.  Anything prior to that and you'd be ok with some moisture as long as it has a chance to dry out.