In general, humans get through life using a sort of shorthand of associated meanings (a phrase can mean a specific thing, as does a particular gesture, colour or sound). Along with stereotypes and clichés, these involve the assumption that the meaning will always be the same.
This can be a very useful thing for writers as it can make our prose shorter and help us to immerse the reader.
What interests me most about readers’ assumptions is that, where a reader hits words that trigger such an associated meaning, a filter kicks in that screens out anything contradictory. This is sometimes not at all helpful!
For example, you could explicitly state that the sky on your protagonist’s world is all shades of beige and taupe, but as soon as you use the word ‘stormy’ readers will generally see shades of grey.
This ‘assumption filter’ is very hard to anticipate, because it’s not always obvious what forms a trigger. I think it applies to all writing, but without doubt creates problems for speculative fiction writers.