10 minutes? Oh neat, that sounds like a nice little snack, maybe a new topic to discover?
Half an hour? Oooh, this could get interesting, this could be a pretty good introduction to the topic.
An hour? Nice, someone clearly did some research and isn't skimping in details! Time to learn something.
Six hours? Holy heck, this topic must be much deeper than I though! This person clearly did some homework and has something to say! Time to get consumed.