The adverb "quite" has the following meanings [according to the Merriam-Webster dictionary](http://www.merriam-webster.com/dictionary/quite):

> 
> 1: wholly, completely ("not quite
>  finished")
> 
> 
> 2: to an extreme : positively "quite
>  sure" —often used as an intensifier
>  with a "quite a swell guy" "quite a
>  beauty"
> 
> 
> 3: to a considerable extent : rather
>  ("quite near")
> 
> 
> 

My understanding is that #1 and #2 conflict with #3. For example, when you say "She's quite right", do you mean "She's completely right" or "To a considerable extent, she's right"? Notice that in the latter case you're not saying that she is *completely* right.

Another example is "I'm quite sure". Does it necessarily mean "I'm *completely* sure"? 

Does the word really have conflicting meanings that can possibly cause ambiguity? Or am I missing something?