What is a machine default?
What a model produces when nothing specific steers it: the most probable answer, given everything it has read.
A machine default is built-in behaviour, not a bug. Agreeing with the person asking, reaching for the safest phrasing and producing the category's most common answer are all defaults, because a model trained to be broadly acceptable returns the centre of what it has seen.
A default is not something the vendor fixes. It is something you direct. Work that nobody directs lands on the default, and work that lands on the default reads like everyone else's.
See it at work
Other terms: Sameness · Brand distinctiveness