I have been pondering this recently, as a new convert to the Style & Beauty forum.
I go through stages with make-up, where sometimes I can't be bothered for weeks and then I wear the whole shebang every day for ages. I don't think 'looking professional' depends on make-up: I would say neat slacks and blouse with understated jewelry and a generally 'on-task' manner counts as a professional appearance.
But I have noticed quite a lot of people who feel they have to wear make-up for work. Is this so in your workplace? Would you care if you were interviewing for a post and a female candidate was bare-faced? AIBU to think you can look totally professional without paint?