That's true up to a point, but many houses decay beyond profitable repair eventually.
It depends how they are constructed and maintained.
In some cultures, houses are not expected to last a long time. Japanese houses famously depreciate with time and lose all their value after about 20 to 30 years.
In other cultures, houses that could last a long time don't get maintained if the people living in them are too poor to do so. Depending on the materials, and construction aspects like breathability, the house could still last a long time, or the materials could decay, crumble, become mouldy etc to the point that the only economical thing to do is tear the house down and rebuild.
Old houses (especially mansions) that are particularly historically interesting or very old may have preservation orders on them, limiting how you are permitted repair and rebuild. Sometimes this means repair will cost so much that only a rich person could afford to do it, and the repaired result would be worth less than the cost of that repair, so the transaction value of the property drops to a nominally low value (it's really negative value), but it's only available to someone who can afford to repair it. These properties tend to be inherited, and then the new owner can't afford to look after them.
It depends how they are constructed and maintained.
In some cultures, houses are not expected to last a long time. Japanese houses famously depreciate with time and lose all their value after about 20 to 30 years.
In other cultures, houses that could last a long time don't get maintained if the people living in them are too poor to do so. Depending on the materials, and construction aspects like breathability, the house could still last a long time, or the materials could decay, crumble, become mouldy etc to the point that the only economical thing to do is tear the house down and rebuild.
Old houses (especially mansions) that are particularly historically interesting or very old may have preservation orders on them, limiting how you are permitted repair and rebuild. Sometimes this means repair will cost so much that only a rich person could afford to do it, and the repaired result would be worth less than the cost of that repair, so the transaction value of the property drops to a nominally low value (it's really negative value), but it's only available to someone who can afford to repair it. These properties tend to be inherited, and then the new owner can't afford to look after them.