All good questions!

The most important thing is how strong the starter is and the number of hours that the dough can have at a temperature in between 22 and 27 degrees C (71-80F). It is at those temperatures that your starter can be active and do what needs to be done to raise your dough.

If your kitchen is cold or your starter is new and not very capable yet, then perhaps three hours at room temperature may not be enough. A lot of people measure things like how much the dough has increased in volume as a way to assess if it had enough fermentation time, and that is what I would recommend: looking for the dough to double, even if it would take say six hours if your kitchen was cold.