Comment by sofixa

For most companies, hiring good quality FTEs is complicated, and very expensive. It makes sense, in many cases, to delegate some things to external vendors ( SaaS companies). There is a line to be drawn somewhere, and it will vary between companies and industries - e.g. a tech company could probably easily handle auth in-house, while i wouldn't expect a law firm or whatever to handle that ( and i wouldn't want them to).