>>> A customer using the same query twice expects the same results for both searches
Of course this is false; please consider:
- customers expect to see in search results whatever new information they added/updated in the system (this is related to "Customers don’t expect near real time updates");
- customers expect "personalized" search results; having built up a history of searches centered around particular subjects (say, programming), you'll expect much different results for "string" than the general population gets;
- customers expect new/more results having logged in, or having gained new permissions/roles;
- customers running "knowledge" or "command" queries ("what is the weather?" "password 16") expect varying results
Or, for a short query string, the user may have a different intent without realizing they've put the same query in.
I might dash off a search for "sneakers" when I am researching footwear. A week later, I might be thinking about movies and enter the same query string, expecting IMDB results.
- customers expect "personalized" search results; having built up a history of searches centered around particular subjects (say, programming), you'll expect much different results for "string" than the general population gets;
Not always the desired behavior. This should be toggleable. It becomes very difficult to find results outside of what google thinks you want.
The gist of this is that customers sometimes re-enter the same query after it failed thinking they'll get what they want the second time. The lesson here is that you can't assume what the customer wants because you don't know. Information needs can be unconscious and contexts between the same query entered twice may have switched.
When the datasets are not the same -- the web is ever evolving, and if I just upgraded Ubuntu, I want the latest results for my search query about why a software package isn't working.
Since there is no mention of a time parameter, these two queries can be separated by a certain amount of time in which the engine learns more about the user.
Perhaps the user is a business user rather than a developer and once profiled correctly results can be adjusted.
Really, this is a falsehood? Like, I want the same query to give the same results given the same dataset always. When do you not want that?