Loading Reporting data: "time frame" "frequency" "update times"

In a requirements package from which I am to design and build BW reporting, information has been provided on "time frame" "frequency" "update times"

Can you share your thoughts on these and how to consider them during the design/build? Examples will be very helpful. Also, how does “time basis” fit in here?

For example what is the implication when on a particular requested report, the frequency= "on demand".

If time frame = quarterly what effect will that be on “update time”?

Which of these speak to when data needs to be loaded into the BW? Which refers to when reports need to be generated? And is there a link between the two?

How is the determination on the frequency and specific time to load data for reporting purposes made?

In general, what influences the decisions on "time frame" "frequency" "update times" during the reuirements gathering phase?