If a person starts thinking like a traditionally-trained professional from the film era, "f/5.6" will start coming to mind in many situations...and with electronic flash, "f/8" will start popping into the mind.
I was watching a Creative Live seminar about two years ago, when Lou Freeman made a statement. She said, to paraphrase, "Your job is not to get the shallowest depth of field, but to make the best possible professional pictures, and when you start thinking 'f/5.6', you'll start making the best possible shots, pose after pose after pose, because you won't have a tiny bit of misplaced focus absolutely ruining shots all the time."
Keep in mind, there's a difference between shooting JUST a face, and a group shot, or a family shot, or a full-body pose that might require three to five feet of depth of field; in many a headshot-type shot, all that is needed is a three-inch deep to five inch deep depth of field band; in a seated pose with legs extended, it might be far better to have five full feet of crisp focus, otherwise there will be disturbing out of focus on extended arms or legs, or areas within the picture.
Yes, learning to avoid the desire to fall back onto a cliched "shallow depth of field look" is something that separates the more-experienced shooter from the less-experienced. At times, having MORE depth of field can add impact to a picture, by actually SHOWING detail and information about the setting or the scene or the location the person is shown in; this is especially true when you want to show context, to show the person in the scene.
One of the biggest laments many people have is when they shoot at a wide f/stop, like f/1.8 or f/2 or f/2.8, and then the so-called best shot suffers from insufficient DOF, and is a garbage frame instead of a real winner.
On-line, there is a LOT of information passed along by noobs, on YouTube, and in blogs, advocating shooting wide-open, even at close distances, when in fact, at close range, stopping down to f/3.5 or f/4 will give almost the same overall look to the shot, but will also give a little tiny bit of what I call "focusing leeway", which keeps a tiny mis-placement of the focus point from being a catastrophic error. With longer lenses, like a 200mm or 300mm, the difference between wide-open and f/4 or f/5.6 is often enough to make it totally,totally worthwhile to shoot at f/5.6. Or even f/6.3.
We now have ISO levels, and portable flash gear, that makes older ideas about what f/stop to use outdated. We are no longer limited to color pictures at no higher than ISO 200 or 400! Ergo...there's NO absolute "need" to shoot at f/1.8 or f/2 or f/2.8 these days, in situations where we can boost ISO to 1,600 or 2,400 or even to ISO 5,000 on higher-performance cameras of modern design.