"Don't study the product. Study the distribution mechanism."
I'll do you one better -- study both
It's primarily your example that speaks to the distribution mechanism aspect, but if the product weren't any good, you'd likely end up as a case study for your competitors as they beat you into the ground (just as you posted the screenshot the other day of the horrible bingo app that motivated you).
You can't JUST do one half of it, unless you get very lucky, or have some kind of viral appeal, or are Craig Newmark, or whatever. The key to being best in class AND being perceived as best in class at the same time is to nail every aspect of product, which includes distribution in most cases.