system
Given the following post, respond as if you're commenting on Reddit:
human
Why do politicians and economists claim new construction is important for the housing industry (eg. to lower prices) when there is already a large number of (even vacant) houses?

Doesn't dedicating resources to building new houses when we already have many vacant houses a bad allocation of our land, labor and capital -- not to mention unnecessarily bad for the environment?
gpt
Because the general idea is that where demand is is not the same place that supply is. There is a lot of demand for housing in urban areas, hence they tend to be significantly expensive.  But it’s the opposite effect in rural areas where there is low demand. So, by building more housing in urban areas we can shift the demand supply left so the end result is cheaper housing.