Why does ChatGPT say “fosters” so much?

The title says it all. Once you read this, you'll start seeing it in so many ChatGPT responses, and it'll stick out.

A bit of a navel-gazing question, but I'm curious where "sticky" and phrases like that come from? Are those words tuned/shaped by OpenAI? Or is there some body of text where "fosters" is over weighted? Would love for LLM experts to shed some light. Thanks!