Just did one of these last week. First issue was that I am quite tall and the photographer was quite short, but he didn't have a step (presumably for health and safety reasons), so to get the angle right he asked me to squat a little. Second issue is that he asked me to take off my glasses to avoid any reflection, but my antique glasses are an important part of my appearance (early-20th-century intelligentsia?). Third issue is that he asked me to show my teeth, but I never show my teeth when smiling (thanks to the NHS I have what the Americans call "British teeth"), so not knowing quite how to show my teeth when smiling I think I ended up baring my teeth instead. The overall effect being an uncomfortable unfamiliar unseeing grimace. I'm hoping great things will come of it.
"British teeth": I thought those were a thing of the past.
They Shall Not Grow Old, Peter Jackson's brilliant modernizing of WW I film footage, has some really shocking teeth. This was before NHS, obviously.
I could never manage to smile with my teeth showing, normally, but I got a guy to film me with my dog, and then it was easy. Doesn't help for the corporate headshot, though.
It was a fast moving corporate production line with a very long queue behind, not a bespoke photo session (I'm not high enough up for that) - less like an agricultural show, more like an abattoir. And the 2 page waiver made me doubt it was even my photo as such.
Plenty of photographers have specials and nice-ish packages where you can get a few basic head shots in 10-15 mins of their time. Don't take this the wrong way, but "put in some directed effort" at this. Don't settle for scraps and obviously ill-fitting freebies given by whatever corporate organized this assembly-line production.